Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

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spinningmagnets   100 GW

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Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Sep 22 2015 9:24pm

$229...I just saw this bike at Walmart...yeah...I know...cheap bikes have cheap parts.

https://www.walmart.com/ip/27-5-Mongoos ... e/45146057

However...I have noticed several new bicycle selections that have 3.0 inch tires in 27.5 and 29 inch diameter. They look very good to me, fatter so you have all the benefits of that, but not so fat as the 4.0's that look kinda cartoonish to me (and are currently overpriced due to being a trendy option). I have ridden several 4.0 tire fatbikes at Interbike, and I appreciate the benefits, but...the 3.0-inch tires are really appealing to me (I am 6-foot tall, 200 lbs).

Dual disc brakes. Needs a Suntour-NCX / Thudbuster suspension seat-post, maybe BMX handlebars to raise grips to where I like them. giant triangle for big battery, straight downtube so it can take the Lightning Rods mid drive, or the new Bafang 1,000W BBS-HD.

The rear drop-outs are flat plates, so water-jetting/laser-cutting steel torque-plates would be a piece of cake, maybe even lengthened plates like the dogman cruiser? https://endless-sphere.com/forums/viewt ... 9#p1008568

For comparison, here is a link to a basic Walmart "Hitch" fatbike with dual disc brakes, but...no suspension fork. http://www.walmart.com/ip/26-Mongoose-H ... d/42248079

Again, if you have the budget to buy a quality bicycle...I have never regretted getting the good stuff. However, I recall a time in my life when I couldn't afford a new bicycle of any price. This might be a good starter E-bike frame for a taller newbie on a tight budget.

Image

edit: went back for pics and details. Bike was in the wrong rack, actual price is $229.

frame: all mild steel from the nose to the tail, verified my pocket magnet on steel and aluminum labelled frames.

rims: 27.5 inch X 57mm outside width, disc only, no rim brake...steel rim, 36H
bottom bracket: 68mm wide
drive train: 3 chainrings X 7-speed freewheel
brakes: cheap cable-operated disc brakes. 180mm diameter disc in front, 160mm rear
tires: both 27.5 X 2.8-inch, frame and fork both have 3.5-inches of airspace width. Should fit 3.4-inch without rubbing (maybe?)

for a triangle battery: inside measurement of seat-tube is 11.5 inches (292mm), top tube inner measurement is 18-inches (457mm) and downtube inner measurement is 22 inches (558mm)

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by DAND214 » Sep 22 2015 10:57pm

Is that the right name? Walmart doesn't recognize that name Mongoose Terrex,

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by rider95 » Sep 23 2015 12:33am

many on here will tell you what a great buy and be sure to put all the batterys hangen off the front forks for best handle rember the most important thag is that its cheap from wallmart

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Sep 23 2015 5:11pm

The frame and fork width along the path of the tire is 3.5-inches, and the pic shows there is no side bulge on the tire yet, sooo...I believe the stock rim could easily accommodate a 3.3-inch wide tire. Rim outer width is 2.26 inches (57mm), so I suspect the inner width is approximately 50mm.

Noticed something odd...the rim has a weak attraction to a magnet. Aluminum rims don't normally, but steel rims have a strong attraction. However there is a strong attraction at the seam. I think these rims are double-walled, but maybe...outer wall that you can touch is aluminum, and inner rim is steel.
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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Gregor » Sep 24 2015 8:23pm

Nice value for a taller rider. The rims are steel you state and that is a bit unusual, but it may have its advantages. I would guess the total wt. is way up there, but I guess that is what makes it a good candidate for conversions. Being disc brake both front and back, you could convert it to 26" with 3" wide tires and have a long wheelbase cruiser.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Gregor » Oct 20 2015 8:33pm

My local wally-world is stocking a 29" x 3.0" huffy called the "Warhawk" and it is $249. To just upgrade the tires on it may cost another $150, but that is the nature of the beast. It has the usual cheap components, but it is dual disc brakes and front suspension.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Teaker68 » Jan 12 2016 6:14pm

Not seeing this bike and limited specs on Walmarts website ordered this bike with hopes of putting in a BBS02-750W. Didn't realize it was a freewheel hub. You guys think I will run into nothing but problems? Have bike here now haven't done anything with it yet. Realized this today when I unpacked bike then did a search that led me here.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Jan 12 2016 7:56pm

It "should" work fine, but...maybe try it out and post the results for the benefit of others who will read here...

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Teaker68 » Jan 12 2016 8:07pm

If you think it's alright I can respect that and will convert it and let you know. Thanks, really do appreciate it.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Jan 12 2016 8:16pm

I think you will find that after you have electric power added, the 7 gears on the rear wheel will be more than enough. I am reading that for off-road, there is a benefit to having a slightly narrower rim, combined with a tire that is wide enough to have a lot of side-bulge, which will allow some side-flex on obstacles (that helps keep the footprint large enough to maintain maximum possible traction).

However, on the street, it may work better to have a wider rim combined with a tire that is not as wide as is normally spec'd. This results in a tire that has a short sidewall, but is wider than its typical mounting. You end up with the extra air-mass of a fatter tire, but it is more stable in fast curves.

So, the stock Terrex tire/rim combo is not bad for the street, but it is not optimal for off-road (based on what some anonymous internet posters have claimed)

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Lurkin » Jan 12 2016 8:32pm

I remember the days of being a student well... involved usually buying other peoples left overs, including inheriting cheap bikes from department stores. They were usually donated because they had issues and were more trouble than they were worth. I found buying second hand bike parts of a quality construction were far better value for money than the cheap stuff, as screws/nipples tended not to round off, wheels remained true, so on and so forth. The frustration levels when servicing it or diagnosing problems were far less.

After reading many build threads on here by people who have purchased Walmart bikes or similar and upgraded parts over time, they usually just wind up with a Walmart frame. If this is your intention, totally with you. If you intend to use it how it is + motorisation.... I'm not with you. I would start by upgrading the brakes as they are the thing you must be able to rely on if it goes a little pear shaped. I have had cheap brakes fail even without a motor/batteries weight and it was a very unpleasant experience. Similarly, I would researching the rims/wheels if you can and make a decision about whether they are actually up to it.

Others have also implied in this thread that a cheap suspension fork is a good thing. In contrast, I would not have one if the damper is rubbish. You just have something bouncing at the front of the bike without really taking any of the hand discomfort out. If its being used as a run-about short distance, a rigid fork is fine and probably better value for money given it does not require additional periodic servicing.

I'm meticulous enough these days that I would be researching each component and deciding whether I would keep it or not, and if not, when it requires replacement and what with. It's a tedious exercise but it can be enlightening as to buying something that is actually very expensive in the long run and takes a long time to really become worth owning.

On a brighter note, BBSXX will definitely fit on here with that BB width without chaindrop or requiring a Lekkie ring. It may be an idea to see if you can get the exact BB offset by way of technical diagram to ensure there is no frame specific offset of the BB, but this would be unusual and unexpected. Further, it can be difficult information to get from a budget bike manufacturer. I had been using mine with the 7 speeds that were available before chain drop.

The magnet may be attracted weakly to the rim if is actually alloy, but has steel spokes and or nipples. I am assuming Spinningmagnets tested this by putting the magnet side on to the rim, it may have this effect.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Jan 12 2016 8:46pm

I'd like to add that I agree with lurkin, about how a used quality bike (that was $500 new) might be better at $250 when worn, compared to a Walmart BSO that is new at $250...

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Teaker68 » Jan 12 2016 11:38pm

My main concern was the freewheel holding up. Seems that most find a cassette far more superior. 750W isn't nowhere close to what most of you guys use but it still going to put some strain on drivetrain. I do own a 8 speed fat tire bike that I converted to a mid drive. Thought this would be a happy medium and as you mentioned could jump up a few sizes with tires. After owning one not really sold on the fat tire bikes. Personally think a studded tire can be just as effective in snow.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by gepinniw » Apr 30 2016 5:23pm

Looking for frames up here in the great white north (Canada). Saw the Terrex at Walmart for $398, plus 13% provincial/federal sales tax. I can accept some markup to account for currency and business tax differences, etc., but this is freakin' ridiculous.
I guess I need to keep an eye out for something used if I want a cheap bike.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Neophyte1 » May 01 2016 3:47pm

Definitely used this bike and slapped on a BBSHD on it
So far I'm having a blast. Removed the front derailluer, attached the stock Bafang kit including the big heavy chainring. Mounted a Luna Cycle Dolphin 13.5 ah 52v battery to the water bottle area. Could only use one bolt due to the shape of it - but it's pretty secure so far and hasn't come loose. I've been able to top out at 30-33 mph - which seems pretty awesome for a fat tire walgoose. There is only front suspension, which I don't mind because I just lift my rear up when I see bumpy terrain coming up - knees provide all the rear shock absorption I'll ever need!

At pedal assist 5 I can cruise at 20mph without any real effort, doesn't start to tire me out until pedal assist 1-2. Throttle wide open (battery topped off at %80, using the Luna Cycle 52v smart battery charger) I can get up to 27-28 mph without pedaling. 25mph at nominal voltage. Based on my last road test I can make it 6.5 to 7miles without pedaling at all.

Been commuting to work across the airforce/army base every day since i out it together less than a week ago and I'm loving it I know I could make it to work and back if I just cruised at 20mph with pedal assist, but it's so hard to not go fast!

As far as the build goes the only challenging part was the bottom bracket. Had to go to the store twice to find a wrench big enough to remove that thing. Luckily I didn't wait too long to convert this bike (bought it with Ebike conversion in mind specifically) otherwise it would been much more difficult to remove - there was already rust and corrosion building up in there. Coated everything with anti-seize and slapped the BBSHD right on. Super easy since the bottom bracket is a standard 68mm.

I really like that it came standard with front and rear disc brakes. I have never had an issue with stopping quickly. The discs themselves were slightly warped, so I did a little unprofessional truing to line them up, and the brakez are within enough tolerance to be rideable.

The BBSHD definitely makes pulling my daughter along in the bike carrier much more doable. I don't pull such crazy speeds with her along, definitely keep it under 20mph.

What do you guys think? This is my first build and ebike I've ever seen/owned/ridden.
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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » May 01 2016 6:11pm

Welcome to ES. If you are saving up your pennies in order to treat yourself someday, I just received my Suntour NCX seat-post a few days ago...Its pricey, but well worth it IMHO. I had a Thudbuster a while back, and I was happy with that too, it's just that when I was shopping last week, I found a good price on the NCX.

I am more than happy to stay at the moped-legal PAS speed of 28-MPH on the street, and at those speeds, a fat rear tire plus a NCX/Thudbuster together make a really satisfying ride feel. I know this doesn't have proper rebound adjustment like a true suspension, but...I avoid potholes, unlike how an off-roader takes big jumps on purpose.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Bullfrog » Jun 15 2017 3:22pm

I bought the Mongoose Terrex and put a EM3ev MAC 12T motor in place of the rear wheel...went with an ALEX MD35 650B rim and a Maxxis Minion DHR II tire in size 27.5x2.8. The triangle battery bag from EM3ev fits nicely inside the frame triangle so you could utilize their large or small triangle battery. I went with a -25R small triangle battery and it works great...I wanted to stay as light as possible. The mechanical disc brakes are adequate if you keep them adjusted properly. I installed two torque arms from Grin Tech....might not need two but I know I'll never have an issue. Where to put the controller was an issue...I finally mounted it in front of the steering head/tube and it has worked great. Get your motor prewired with thermistors and buy a Cycle Analyst....a little pricey but you won't regret being able to keep up with everything via the CA. I went with the CA v3. I don't have pedal assist just a throttle....can't remember which CA that means you should buy but Grin Tech can help you.

EM3ev was phenomenal in walking me thru the selection process...this was my first exposure to any kind of ebike. I would very highly recommend EM3ev.

One question I have....has anybody upgraded their fork?

If yes, what works and what specs do I need to look for in a new fork? It gets tricky because the front hub is 110mm which means boost spacing and I may want to go to a 3.0 Maxxis High Roller in the front at some point. Boost spacing forks are slowly coming out but I wish they would catch up with the demand. I have a Suntour XCR on a 29er that works OK and I was going to go with one on my Terrex but Suntour doesn't make one that will fit. Looking for a plan "B" that won't break the bank.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by spinningmagnets » Jun 15 2017 3:44pm

I installed two torque arms
You will never regret this. TA's have no moving parts to wear out, and when this bike is old and worn out, the TA's can be transferred to another bike. There is a chance that only one TA might have "been enough", but my attitude about this is...what is the cost, compared to the possible consequences? The cost is cheap, and the consequences of a "spun axle" is many dollars and lots of my personal time wasted.

What brakes are on the Terrex?

I recently rode a bike that had the front disc upgraded from 180mm to a 203mm diameter disc, and the cable-pull caliper was swapped to an Avid BB7. I assumed the brake was hydraulic because of how awesome it felt. The main benefit of the BB7 is that it has a knob for adjusting the pad wear, instead of needing an allen wrench. (doing this requires an adapter to move the caliper farther out away from the axle).

The broad and flat rear drop-outs make this a decent candidate for a rear hub (if the height of the frame fits your body) and the straight downtube, plus the 68mm width BB makes it easy to fit the most common mid-drive kits. When the rear tire wears out, you might consider swapping-in a 26-inch rim with a fatter tire (which should result in a tire OD very close to the current state)

Steel frames are heavy for a pedal-bicycle, but...once you know you are going electric, there are several benefits to using a steel frame.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by cal3thousand » Jun 15 2017 6:00pm

I like the flatness of the dropouts; making torque plates for odd shaped dropouts is a pain in the ass. This one looks like it would be very easy for a noob to fit something strong without even drilling.

Good job on bringing the caliper with you :D
Get a Cycle Analyst and a Multimeter, you're still a noob if you don't have at least one of each.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Bullfrog » Jun 21 2017 6:51am

The brakes that came on my Terrex are Mechanical discs (cable operated) with approximately 160mm disc on the back and 180mm disc on the front.

I can't find a brand marking of any kind but they have worked very adequately for me....I did spend a lot of time getting them adjusted i.e. straightening the discs, centering the calipers on the discs, and adjusting them so there is as little clearance as possible between the pads and rotors.

Has anybody upgraded their fork or disassembled the fork and been able to improve its operation? Mine sticks terribly and has absolutely no rebound damping. I can live with the "No Damping" but the sticking has to go, one way or another.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by SprocketLocket » Oct 24 2017 6:57pm

Please, what is the rear dropout spacing?

It is encouraging to see people finding and reporting to the community, cheap Plus bikes which are using more STANDARD sizes! Man, almost all of these Huffgoose Plus bikes use oddball bottom brackets like 73mm, and weird rear spacing like 155 (never heard of either!). If this is 155, how could it be (or could it be reliably) widened to accept a 170mm hub (and still hav the disk brake line up properly)?

I have read that cheap suspension forks should be dissembled before use, and properly lubricated. I read of a guy putting little disks from skateboard trucks at the top and bottom to soften any bottom-outs (I'm having trouble visualizing this, but thought I'd pass that on). Does anyone know the brand/model of fork? Mongoose uses Suntour and Kolo a lot. I've surmised from reading that the Suntour XCR is the lowest of the forks that get used, which is passable. I am sure some Mongoose and/or Huffy models use the XCR, but did not write it down.

The reason more people are looking into these bikes, is that you can't get a cheap used equivalent of these. Fat bikes are fairly new, and Plus bikes are even newer. Owning a fat bike (purchased without ever having ridden/access to one), I now think Plus bikes make much more sense (also not having ridden one, but now knowing the benefits & downfalls of huge tires). I am personally more interested in 26Plus, but that is (of course) the newest to be introduced (as if coming full circle), "bleeding edge" again. I am composing a list of cheap big box Plus bikes. There are far more 27.5+'s than 26Plus or 29Plus.

The thing buyers are forgetting, is a 26Plus is going to basically have the height of a normal 27.5; a 27Plus is going to basically have the height of a 29er, and a 29Plus is going to have the size of a wagon wheel.

For wider-tire ebikers, we should really be interested in the 26-inch format, as it provides the lowest height (beneficial for e-motors liking higher RPMs) for having a wide tire, as going wider also means going taller, and already a 26Plus is pretty high. And out of the range of what most ebike motors are really designed for.

On the Terrex rims, they have spokes which are quite offset from each other. I would think that would lend to better stability. I have seen "low profile" spoke setups on wide-tire bikes, such as the Mongoose Bering. It seems that the low profile spoke setup may be to prevent the derailleur from getting sucked into the spokes. I have heard of 27.5Plus Mongoose owners having this problem; if anyone has experienced this, please say so.

The other benefit of these cheap bikes is they usually use old-school 36 spokes, which ebike hub motors ALLLL do. If you're buying the motor already laced into a rim, it doesn't matter. But if you want to re-use the rim, it matters a lot.

So my last question is, what 26-inch rim (preferably brand and model, and even 36H hub, if you have an idea) would you recommend for a 26x3.0 or 26x2.8 conversion for this bike? Actually, I have a 32H fatbike (170mm QR rear) I'd like to convert to 3-inch in the rear. (I also have a MAC 12T, love it but find it a bit slow now.) If I need to get a wheel built, maybe even have a rim anywhere from 32mm to 40-something mm, so I could also use a 2.2-2.6 range of tires on there, if I wanted? I think 50mm is awesome if you want to go FATTER than 3". You can do 3.5 (ideal width), and I think even 4.0 with them. But not so good if you want to stray the other direction. I've invited some earlier participants to revisit this topic as well.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Bullfrog » Oct 24 2017 10:18pm

Well my Terrex has a 68mm bottom bracket. The spacing for the rear wheel depends on when you bought your bike....my first one has 135 mm and my second one is 148 mm, both pretty common.

As far as 26 plus being "The size", I don't think you can make that statement across the board for everyone. It all depends on how you are going to use your bike. I have a Mongoose Hitch (Fat Tire) and the Terrex 27.5+...currently running 3.0 rear and 2.8 front. Depending on conditions, they can both be terrible or perfect.

Electric motors including the MAC are more efficient when spinning close to their designed full speed rpm. A smaller diameter wheel will help you get to that rpm....so your comment on 26+ is somewhat relevant. But why stop with 26+, I am currently building a Terrex with a 20x4.0 rear tire and I should have a top speed of about 20 mph when completed. How the bike will handle...well that is a different story.

Wheels...well it depends, EM3ev builds great wheels and you just slip your MAC motor in the hub. You can buy the entire motor/wheel, just the rim, or anything in between. Cost is reasonable and they have a good selection of rims in all diameters. My first one was a 34mm internal width 27.5 rim, second one was a 20"x32mm internal width, currently ordering a 20x57 mm. Just depends on how fast you want to go, how much waste heat you can stand, and how gentle you want to treat your motor. With the 27.5 wheel I could run about 31-32 mph without the motor getting hot...on flat ground. There are a bunch of other sources as well but EM3ev has been my go to source and has been very reliable and delivered a quality product.

Another variable you didn't mention is batteries. 52v will turn any motor faster than 48v. 48v will turn any motor faster than 36v. But the cost and the weight go up with the voltage. You also need to match your controller, your battery, and your motor within reason.

The big advantage of a BBSHD is you can use the bike's gears to get the motor rpm up in the efficient range. The downside is all the power is transmitted thru the bike's gears and they were designed for one human power not multiple horsepower. So in conclusion....it depends :D .

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by wesnewell » Oct 24 2017 11:30pm

I know nothing about the Terrex other than what's on the ad. My choice was the Huffy Fortress 3.0 with a standard width mxus 3000 motor. Info on that bike is here;
https://endless-sphere.com/forums/viewt ... s#p1182072
Need Advice? https://endless-sphere.com/forums/viewt ... =3&t=66302
Mongoose 26" Ledge 2.1 mtb bike $99, yescomusa.com 48V 1000W rear hub kit $200, Hua Tong 72V 40A controller $35, 10ah 24s lipo $217=~43mph, range=45 miles @ 20mph. 25K miles and still going strong.
Huffy Fortress 3.0 with MXUS 3000 4T motor, 24s lipo, 96V 60A controller. Total cost with extras <$700. Top speed ~50mph
My videos https://www.youtube.com/channel/UC0KW4U ... _G2wQhptMg

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by Bullfrog » Oct 25 2017 2:39pm

Check with these guys on your MXUS and how to hop it up, what works and what doesn't....they have been racing them for a while: https://www.westcoastelectrics.com/

The Terrex is a steel framed, 27.5" wheels, 180mm front/160mm rear disc brakes, 2.8" tires, 52mm internal width rims, Mongoose bike. IMO it is a pretty good bike overall. The steel frame is the best part and what I wanted. The fork is not very good....just like all big box bikes. Makes a good start for most builds and was selling at Walmart for $222. USD.

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Re: Frame candidate, Mongoose Terrex, hardtail 27.5 X 2.8

Post by SprocketLocket » Oct 26 2017 7:04am

Thanks for the great info, bullfrog.
I know and agree with pretty much everything you said. I get criticized for being too long-winded, but then when I simplify/shorten things, I then get "corrected", lol.

EM3EV does not carry any 26er rims between 32 and 80 mm. At least, they didn't when I bought. I'd be gleeful if I were wrong now, but I don't think I am. It's just a huge gap. Before Paul sold fatbike kits, and then while he was preparing, I encouraged him to choose 50mm as the fatbike rim, if not something in the 60-ish range, for fatbikes, not 80mm. Or, I said, if you carry 80, please carry something between 32 and 80. You can see that already, I was looking towards Plus bikes, which were so nascent they didn't even have an agreed-on name. I tried to tell him that the 50-ish/60-ish rims are much more versatile, and that there were "fat" tires less than 4-inches. "Mid-fat" was a term I'd heard, and I don't think I'd heard the term "Plus" used yet. People usually called them "fat" (there was less distinction than now). And indeed, fatbikes rims did indeed start in the 40mm range (44mm SnoCat was 1st commercially available fat rim), and even a Large Marge is in the 60s (65 to be exact). IMO, for most fatbikes, 80mm is not necessary, and indeed a hindrance, unless there is a fashion statement to be made, or people feel they need the back to look like the front, but I think of ebikers as more nonconformists.If you want to go 4.8 or 5 yeah you'll want 80mm, but those are fairly rare, and were almost unknown at the time, and most LBS's didn't even have a single vanilla fatbike in stock. Paul didn't go with my advice, obviously. It was not easy, because the 36-spoke was not used much on wide-tire bikes, so there was/is a very limited rim selection (hence the reason I put out the call in my last question in previous post). I'm not entirely sure of Paul's thought process, but I know he wanted a strong rim, prefers to buy from AlexRims due to a known quality/strength/price combination, and IIRC, AlexRims didn't make something in that (~50mm) size at the time--and I am still not sure if they do (their website sometimes makes deciphering inner widths difficult). They did make an 80mm Blizzerk in 36 spokes, and that's what he went with. Paul told me it was strong, and he was right. It would be easy for tubeless, as there are NO weight-saving cut-outs in mine. Full-fat wheelsets are ridiculously heavy, even before you add liners and/or sealant to prevent flats. I want some width, but the height, width, and rotational weight of 4-inch tires is more than I need or want. I don't know how pedalers ride these things without assistance. If I run my tires at the comfy low pressure pedalists claim they normally do, my controller gets pretty warm just casually riding around, flat, and my voltage goes down strikingly faster. If I pump up the pressure, it's basically room temperature doing the same, showing me how much more energy low-pressure riding takes, even further baffling me how these fatbike pedalers do it!

I just spent some time re-aquainting myself with AlexRims.com. It does look like AlexRims now makes 40-something mm rims, but ONLY in sizes taller than 26er--which really suxxx!! I couldn't find anything 40-ish for 26 (I'm hoping someone will contradict me). In 26, you can get 32, 34, and 35 (a lot of choices in a small range)--and then--nothing, until 70mm! So there is still this huge gap that I've been talking about. What, we need a hundred choices between 17 and 25 mm, yet we have to literally "double it" to go to the next step from 35? This is, honestly, why I asked for advice.

So, while I'm glad to see anything less than 80mm, I really don't get why AlexRims would do 70mm (so close). And not something more between 32 and 80, which was their gap when I bought (which was even worse, but not much worse). The average between 32 and 80 is 56, BTW, i'm just sayin'.

It's really maddening, b/c they make 40, 45, and 50 mm rims, but NONE for 26ers. Why can I get a 50mm rim in 27, 29, and even *24* inches, but not 26?! Why can I get a 40mm rim in 24-inch and even TWENTY inch--but not twenty-six?

Some of AlexRims naming baffles me. For instance, "Supra35"-- its specs say 559x30mm. So why not "Supra30"? Yet, DX32 is actually 32mm ID. XM35 is 35mm. You would think the Volar 3.0 would be for a 3.0-inch tire, right? No, it's 30mm. The SX44 is--you guessed it--20mm.

Update: hey now, what's this. Okay, more naming weirdness:
Specs on the "Blizzerk 80" are 559x73.
Spec on the "Blizzerk 70" is 559x64. Huh?
So, the "Blizzerk 70" (64 actual) is basically equivalent to a Large Marge (65).
Okay, so 35-65 is their (AlexRims') gap now. That's still a huge gap.

35 could do, though. You could run standard MTB, up to 3.0. I don't think I'd feel comfortable running my 3.5" Sunlite Speedster on crushed rock/unpaved roads though--- or am I being overly cautious?


For Newbies:
Regarding the rear spacing of the Terrex as Bullfrog noted.
A lot of newbies doing research may think of buying what they think is a 'standard' mountain bike (if there is such a thing), not realizing that the spacing may not be matching axle shoulders of the motor they got. As far as I'm concerned, WesNewell is the expert on getting motors to fit into frames they aren't sized-for, so I would point to his posts for newbies who may have gotten into a... jam (not jam nut). 148mm should be the new 'Boost' spacing... whether Terrex really fully follows the Boost standard, or is just 148mm, or whether that even matters, I don't know. How doable it would be for mechanically-wary people to fit it onto a 135mm motor, I don't know. Some cheap Plus bikes are using 155mm rear spacing; I really haven't heard of this elsewhere. Also funky bottom bracket sizes. You'd think it'd be cheaper to just stick with established tooling. I don't know what is up.


After doing some research, I am here on it:
These 2 videos pretty much de-convinced me to keep researching in this direction (right or wrong):
Huffy fortress
https://www.youtube.com/watch?v=N_fcNixfU-c
Mongoose
https://www.youtube.com/watch?v=5S78kVm7RtY

And this one made me realize something and decide that I, personally, will probably never buy a bike with rim brakes.
I do hear that rim brakes actually perform better on the cheapest bikes than the ones with disk brakes--issues like the disk bending the fork to the left, causing self-steer; rotors out of true, difficulty adjusting, etc. However. The risk of overheating (or other malf's, like pad rubbing on tire) to total failure is much much lower.
Will a Walmart Huffy survive a Downhill Mountain Bike Trail? | Skills with Phil
Watch out, it's about an 8 on a 10-scale pucker factor:
https://www.youtube.com/watch?v=wkMnk_e ... KzvgUy0zGW
You may say, "He rode that bike in conditions it wasn't designed for". Yeah, but what are we doing with ebikes?! Being able to go 30 is pretty dommon outside of entry-level, torque-oriented, and socialism-marxism-fascism-leftism-authoritarianism-loving, lawfully-castrated eURO-bikes. The increased range and increase in sustainable speed gives us the ability to access places we couldn't before, including areas where we might have sustained downhill. The cheap rim-brake bikes are clearly not up to sustained downhill, especially on the original pads. The FIRST upgrade you should, no MUST do as an e-biker, in my non-expert but researched opinion, is get quality 3rd-party replacement pads. I hear it will also help on that horrible noise. This bike isn't alone on this. They all do it. Here is WesNewell's Fortress. Wes if you read this, respect. Just linking as an example of the sound, which, in fairness, you said in the video you were planning on getting better pads too. [Note: actual pics of the bike is at the very end.]
MXUS 3000 on Huffy Fortress 3.0 24s lipo
https://www.youtube.com/watch?v=w97n4ig8254

A Mongoose Ledge dual suspension fares better in the first videos here. But only after a complete rebuild of the bike. This shows me that whoever is buying these bikes, should basically have full-fledged bike mechanic skills (and the patience required to do so), or be having sex with someone who does. The sad thing is, most people buying bikes like these, and who I think the bikes are really aimed at from a marketing standpoint, are at the opposite end of the spectrum.
Cheap Bikes & Torture Tests [playlist]
https://www.youtube.com/playlist?list=P ... d5L7BsyLRF
This video series also caps my thoughts on entry-level "MTBs": IF you fully tune/re-tune them/maintain them, and IF you keep your riding LIGHT DUTY, AND with a little luck, you'll probably be okay. One thing I don't think anyone will dispute me on, is that (aside from the frame itself), if you test the limits, the components (including critical components) are much easier to damage or break completely, than a higher-quality bike. Basically, the threshold is crossed sooner. And it will almost certainly take more maintenance along the way.

One of the most interesting videos is of bike tires being completely filled with WATER, and ridden, to see how much heavy wheels really affect performance.
https://www.youtube.com/watch?v=vq7fF0_ ... d5L7BsyLRF
A really interesting thing is, once he was going, things actually felt pretty normal. It was stopping, starting, and trying tricks that needed lots of effort. That seems to match my observation that my fatbike's battery goes down noticeably faster with more starts and stops, no matter how gently I try. I was still amazed at some of the tricks he could still do with water-filled tires.

The final video is '$149 WalMart Enduro bike', or something like that. I want to share my main pick-up there too. 2 trail-biking enthusiasts took a trip to remote & rough Pigsah Nat'l Forest bike trails, and for whatever reason, instead of bringing their good bikes, they bought $150 bikes at the local Wal-Mart. The INTERESTING thing is, they both bought the SAME model [Genesis brand, dual-susp, front disk, threadless steerer]. While they both made the trip together, the cameraman rode faster & harder, just going for it. The buddy tended to lag behind, not pushing the bike as hard. Interestingly, by the end of the trail, the cameraman's bike was completely ruined in multiple ways, while the lag-behind buddy's bike was actually still completely operable! Actually with nothing broken. Same bike model, same assembly line, same trail. This is really interesting, because it nearly pinpoints a fine line between "it's fine", and "total disaster", including very real safety risks (especially since there was no cellphone service, nor emergency vehicle access, on the park's trails). I realized that, by definition, all ebikers are pushing their bikes harder than normal riders. But some people are riding fairly gently, with medium power, on good pavement. WesNewell's suburban riding videos come to mind. But when you're often riding on farm roads, crushed rock, jarring dilapidated pavement, and the occasional bumpy field, like me, things change. I'm reminded of why I bought a front-suspension fatbike in the first place, not that I really knew what I was doing (and I knew that). And for trail riding, well, clearly, all bets are off.

While this is long, I don't post often either, so I put a lot into each post. I hate to say this, but this spate of research has made me appreciate B*kesD*rect bikes more. As much as I dislike the company's marketing strategies, the sales/support staff who are completely inaccessible by phone and randomly blow you off by email, I even dislike the website.. what I <i>can</i> say is, the bikes are solid compared to these entry-level big box bikes, and most importantly, generally not a danger to you as a person--where that certainly cannot be said for far too many of these big box bikes, especially how they're delivered. I'm surprised a class-action lawsuit hasn't arisen yet. Some of the QC stories of these Chinese bikes are just egregious. And it should remind us to always resist socialism/marxism; whatever's going on over there-you don't want it here.

In the '$149 WalMart Enduro bike' Pigsah Nat'l Forest video, this line pretty much summed it up, regarding one bike being completely destroyed, and the other completely fine:
"...it was clear that speed was the major disruptive force on these bikes".
Obviously, he means how hard it's ridden, and in his case, going faster meant more stresses on the bike. And the stresses weren't coming really from the speed itself, but the impacts; however the speed made it worse. It's kind of how comedian Ron White said, 'in a hurricane, it's not the wind that kills ya. It's the stuff IN the wind.' But--speed makes it worse. And speed is what "e" gives us. Range, too. We're going farther, which means more variety of terrain. More uh-ohs, "oh shit" moments, and hitting them harder. I remember I spent the (to me) crazy cash on my bike with bleeding edge features for perceived safety improvements. Buying an entry-level big box Plus bike just for the tires, and tubes, and lace-able rims is tempting, I'll admit--with a frame left over for maybe a 2nd build/to experiment with. I thought I'd probably upgrade the fork and handlebars. But after watching the video, I see now that most of the cheapos have scarily fragile handlebars and quill stemps/headsets--not more-confident threadless steerers. I didn't even know what any of this crap was when I started considering ebikes!

So now, yeah--if I actually thought I might do a conversion to an entry-level BBB [big box bike--there is a forum called bigboxbikes.com, actually], my minimum standard would be disk brakes and threadless headset... which will disqualify LOTS of models. Oh well, probably for the best. Originally, I thought: replacement handlebars are super-cheap (and they are). An ok budget suspension tube ain't much, either. And yeah, the bottom brackets are weak, but I won't pedal much. But then I see that the hubs are also fragile (and definitely need checking/adjusting before riding--beyond most rider's skill level). Okay, the rear 'hub' will actually be the hub motor. Still leaves the front hub (not as big of a deal IMO). Even if just left with the frame, you're still stuck with the overly-weak headset--yikes. Hm.

Also in fairness, in the 'Cheap Bikes & Torture Tests' playlist, the author reviews a Mongoose Dolomite, which broke the Big Box trend by using fairly standard, simple, and durable components--albeit with an inexplicably high-toothed front sprocket. What I drew from this was, a budget mfr can make a reliable, "dare I say, 'safe?'" [quote from the video] cheap bike if they want to, if they keep the gimmicks low, and focus on simplicity and reliability [ridiculous 100mm-rim fat tire gimmick aside].

And, interestingly, WesNewell owns 3 of the 5 bikes reviewed in the above videos. No disrespect, Wes! LOL. Wes was actually important to me and the start of my e-biking. Of all the prominent members here, he was the actually first ebiker I actually zoomed in on. It was due to his signature at the time. He had one bike, and included basically his whole recipe in his signature, which gave me my first real starting point. I really hadn't found full 'recipes' anywhere else. And, like most of us when we're first getting into this, and experiencing 'sticker shock', his 'recipe' was budget-oriented, so less of an initial turn-off, which may have kept me in the game. I strongly considered his recipe, but ultimately began modeling off Neptronix 'recipes', as I began to talk myself into spending 'beaucoup bucks'.

It was, however, almost immediately clear to me that, despite WesNewell's budget approach, he'd forgotten more about bikes than I ever knew. He had enough spare parts from upgrades to build a spare bike, and the knowhow to do it. Whereas, I didn't own a bike. At all, much less spare parts. Nevermind the knowhow. So I somewhat blindly spent more on a bike, somewhat compensating knowledge for money. Now that I know bikes better, the more I researched low-end mountain bikes, the more I began to appreciate mine. It really is a solid bike. And if I didn't have to have the fancy suspension, I could've gotten something just as good, maybe even better-suited for me, for less than half the price, or a few hundred dollars. But that's still 2-4 times more. And while I'll won't controversially say 2-4 times better, I will entertain maybe "2-4 time safer", or likelihood of something going dangerously wrong.

I know there will be newbies doing research, finding this thread doing websearches/all-night research, like I think we've all done on multiple occasions. This was long, but after having gone from zero to actually having some wherewithall, I try to give back with hopefully-accurate, well-reasoned POV's, after being helped so much by others who did the same before me.

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