Front Fork replacement

[Kingfish]

I used the Marzocchi 44 RLO Bomber Fork: Takes either disc caliper or rim brake. Tough mofo for even my road trip. Completely adjustable. I think mine was the 2010 model, though can't recall if it was the 100 or 120mm travel. The headset employed was the top-of-the-line Cane Creek 110, with internal ceramic bearings. For torque arms I designed my own and had one mounted on each side.

Custom torque armsmounted to the Marzocchi 44 fork.

I beat the hell out of these forks with the load I was carrying. They are very solid and worth the money.

~KF

 

[Brentis]

...
I disagree that a better feeling fork is a waste. But I agree with Mad Rhino that too much travel for the frame would be dumb. On my cheap mongoose, I replaced cheap 80 mm with 120 mm that feels a ton better. Big improvement. Trying to ride the mongoose frame into the dust, but so far it seems fairly impossible to actually break it. Perhaps the same will be true of the genesis. Cheap junk, but tougher than you think?

I dont think I fully expressed my thought.

While any new components will be an upgrade to the very basic components equipped on the Genesis.
The real ? is whether that frame is capable of the 40mph beating BoppinBob is putting to it.
Walmart Canada offers a different selection of bikes than the US.
We dont get the mongoose or genesis so I cant say for sure, but from my experience with cheap Chinese box store bikes.
Check all the welds & alignment of the particular unit you pick. I have found great variations bike to bike.
Incomplete welds painted over, blow/burn through welds, hammer/tooling marks, etc.
You really need to inspect closely. I had to sell/trade this bike because of it.

Even my "ScootBike" frame suffers from what my untrained eye, is poor welding.
I would/could not comfortably run an un-inspected Box store bike frame @ 60kph even if you upgraded every component.

Now rather than dropping $1000 on fork, shock, brakes, drivetrain, on a $200 shit frame.
(He wants a new fork now, but those brakes will soon be toast, & the drivetrain is probably already "talking")
Buy a used DH/AM ,freeride, slopestyle, whatever, with all the quality components already there.
Trek,Giant, Norco, etc.. Get friendly with Pinkbike, Craigslist,etc.

If the Genesis frame is strong enough & is better suited to battery placement than the "quality" bike.
Strip the quality bike of the components you need, & sell the frame/parts.
I think you will find that all "quality" bike frames will be superior in every way to the genesis frame, with the exception of battery room.
Make a list of the things you need/want, quality fork 100mm-200mm travel, hydro brakes, air shock, appropriate dropouts, etc.
Good bikes can be found for between $400-$1000+ just be patient, keep searching the ads, then pounce.

Good luck

 

[dogman dan]

Oh, I do agree that the genesis is craptastic. I looked very close at them at my WM, and rejected them as too weak for much.

Then one showed up at the races, and did quite well at blazing speeds. My fave, the mongoose blackcomb, I simply do not trust above 30 mph. You can just feel it flexing away under you, side to side. That's very typical of the wallbike category. Not what I want to dive into a corner at 40 mph on.

I totally agree don't spend a thou on upgrades. A good crankset from a vintage but quality mtb, $20, maybe $40 if other parts on it are worth scavenging. Then up to $200 for a decent entry level fork with tunability, like a used bomber. Another $100-150 for a rear shock, if you find one that fits. No more. No juicy disks, or better shifters.

 

[MadRhino]

Relativity, everything is about one's requirements and riding style. I start with 5000$ + bikes and gladly spend a few K on upgrades, ride them one or two seasons at bike parks, then build it to an E-bike to ride the close by mountains that have no chairlift and facilities. Then, Ebike performance has nothing to do with quality, for there are some here that beat me to it with a cheap frame, average components, and fabrication skills. Quality is required when you ride rough terrain and hit hard, that is where nothing is too expansive if it can save your bones.

 

[chroot]

I agree, First thing you need understand Farfie spent lot R&D on some crap cheap bike and only one came out strong enough is Genesis V2100 MTB. He beat it up real good and the frame didnt break down or crack the frame at all. It passed the Farfie's quality control.

I do have Genesis V2100 (3 of these) with Farfie's custom extended swing arm waiting for cromotors coming from Zombiess. I replaced the front fork to Rockshox 120mm and the rear shock replaced to Fox air shock (Nephonix posted the link in sale section). HOLY CRAP big difference and the riding comforts so superior. Hey I cant complain the costs compare to brand new full suspension MTB worth 1500-2500 bucks. It's about bang for the bucks. :lol:

Lastly, I don't know some of you knew I commuter to my work at the UPS and I am the speedster guy riding 40mph EVERYDAY and YES I SAID EVERYDAY! I abused my ebike hard and i took them everywhere include big city like SF with bad roads at high speed.

Everything still solid no break down except tire tube blew up caused by hit the pothole. That's it! 8)

While any new components will be an upgrade to the very basic components equipped on the Genesis.
The real ? is whether that frame is capable of the 40mph beating BoppinBob is putting to it.
If the Genesis frame is strong enough & is better suited to battery placement than the "quality" bike.
Strip the quality bike of the components you need, & sell the frame/parts.
I think you will find that all "quality" bike frames will be superior in every way to the genesis frame, with the exception of battery room.
Make a list of the things you need/want, quality fork 100mm-200mm travel, hydro brakes, air shock, appropriate dropouts, etc.
Good bikes can be found for between $400-$1000+ just be patient, keep searching the ads, then pounce.

Good luck

 

[Brentis]

Hope I didnt come across as shitting on the Genesis.
As an average commuter ebike it is probably fine. (As a 40+mph race bike, I think maybe pushing it)
Considering bang for the buck this seems to currently be thee platform.
A proven linkage based rear suspension, a frame that is strong enough & offering battery space.
To make it a proper race bike Farfle had to extend the wheelbase & upgrade components though.
I think the bigger factor in his success was motor/batt/controller & rider.
Never underestimate the skill of the rider in moto or ebike racing success.
I believe a great rider on an average bike, will beat an avg. rider on a great bike.
I dont recall anyone raving about what a robust, laterally stiff frame the genesis is.

I just wanted to warn about the possibility of spending more on replacement parts, than a good used bike costs.
It can get real easy spending more upgrading a Box store bike than just buying a proper used mount.
Sometime spending a bit more money up front, saves you cash in the long run.
God knows I have been trying to do it cheap my whole life. :wink:

Looking back how many of you would have spent the total eBike budget differently now?

 

[dogman dan]

Yes, I do agree, when buying used stuff to upgrade a bike, get the 20 buck price for half a bike that has the part you need. Beats the 100 buck price for the same part in the same condition, from a guy who parts out stolen bikes for a living.

But if he doesn't go crazy with the prices, upgrading the worst stuff on the genesis will ride better. Those craptastic forks simply gotta go!

I find the big deal with those cheap frames is when you try to carry a lot of weight on a rear rack or panniers. A cheapie frame will start doing high speed wobble crap at very slow speeds. But that's not a big issue if the battery is carried in the frame.

Definitely a screaming good deal on a similar but better frame would kick ass on the genesis. But who's selling thier kona dawg frame for $200, or the whole bike under $500?

 

[auraslip]

I have the same fork as kingfish. The 44 RLO bomber. I picked it up new for only $250. It's my only REAL fork I've owned. It makes any wally-world fork look like a toy.

BUT I'm looking to upgrade it. It flexes when I ride. Even on smooth pavement it flexes forward and backwards. And it doesn't really soak up small, quick bumps. I think that's a problem most forks may have since they're tuned for off-road riding. It is light years ahead of the suspension forks on wal-mart bikes, but it's pretty bottom of the line. I really want a fork with a through axle. It's supposed to provide extra stiffness that a QR axle simply cannot.

Anyways, I'm looking for a stronger fork in the $500 range, used or new. But the problem here is that my frame is setup for 80mm forks - 100mm max. And this is a problem most low end bikes and non-off road bikes will have. If you use a fork with too much travel, it changes the geometry of the bike. This can put a lot of pressure in the wrong areas and potentially crack your frame. It also makes the bike handle like shit. I'm thinking maybe running a smaller front wheel will make using long travel fork acceptable, but I'm not sure.

Another option is the rockshox TALAS system that allows you to adjust the travel on some forks all the way down to 95mm.
Another option is dirt jump forks. They are usually 80mm to 120mm. But I understand they're designed to soak up big hits, and not a bunch of smaller hits like you'd find on an ebike.

I don't know. I'm really lost here. Finding good information about bicycle suspension online means digging through a bunch of peoples opinions about how their forks work for them. Dammit. Why can't bicycle forums be more like the ES where engineers pick apart components objectively!

 

[Brentis]

...

...

I don't know. I'm really lost here. Finding good information about bicycle suspension online means digging through a bunch of peoples opinions about how their forks work for them. Dammit. Why can't bicycle forums be more like the ES where engineers pick apart components objectively!

You have to take "their" advice with caution.
We generally add 50+ pounds to our bike frames. Often in places which affect handling/fork function.
Not that the advice is bad, but would be underrated for our application.
Best to ask the pro's around here, LFP, MadRhino, GCinDC, etc. Guys that are going fast & hard.
Generally a DH mountain bike fork, with ride height adjust ability. So you can hit the sweet spot with your frame geometry.
Just a couple of thoughts.

 

[hjns]

Some more thoughts...

I recently temporarily replaced my Fox F100 Terralogic (100mm, used to cost > $1000) with a used Rockshox Reba SL dual air (100mm, costs around $150 on Ebay) because my Fox needs a service (oil leaking problem, well known for this fork).

Playing around with different air pressures in the Reba gave me almost identical feel as the much more expensive Fox during my commute. As my commute is mainly on tarmac with some nice holes in the roads, I never bottom out on the 100mm suspension on either fork. I also make sure to set sag at 25% with me and the battery pack in riding position. I also found that I set rebound at it's fastest for both front and rear suspension.

Anyway, I think that for normal commuting (without running up and down stairs like GCinDC), a low price fork ($150-300) with adjustable sag and rebound should suffice for a bike up to speeds of 40mph. The main advantage of my Fox is it's extreme light weight, which fades away relative to the weight of the motor and the lipo pack. However, if you are going to jump, do other techy off-road stuff, go higher speeds, etc, you may want to get a dual crown large travel fork.

 

[MadRhino]

Yep, the Reba dual air is a very good fork, and the weight is close to a Terralogic F100. Both are high maintenance, but I'd prefer to do the frequent oil and wiper change with the Reba, than rebuilding the Fox twice a season.

4 inch of stiff travel is perfect for the road with our Ebikes, and we shouldn't pay the extra for a fork that has its only advantage in pedal competition.

 

[Kingfish]

I have the same fork as kingfish. The 44 RLO bomber. I picked it up new for only $250. It's my only REAL fork I've owned. It makes any wally-world fork look like a toy.

BUT I'm looking to upgrade it. It flexes when I ride. Even on smooth pavement it flexes forward and backwards. And it doesn't really soak up small, quick bumps. I think that's a problem most forks may have since they're tuned for off-road riding. It is light years ahead of the suspension forks on wal-mart bikes, but it's pretty bottom of the line. I really want a fork with a through axle. It's supposed to provide extra stiffness that a QR axle simply cannot.

Anyways, I'm looking for a stronger fork in the $500 range, used or new. But the problem here is that my frame is setup for 80mm forks - 100mm max. And this is a problem most low end bikes and non-off road bikes will have. If you use a fork with too much travel, it changes the geometry of the bike. This can put a lot of pressure in the wrong areas and potentially crack your frame. It also makes the bike handle like shit. I'm thinking maybe running a smaller front wheel will make using long travel fork acceptable, but I'm not sure.

Another option is the rockshox TALAS system that allows you to adjust the travel on some forks all the way down to 95mm.
Another option is dirt jump forks. They are usually 80mm to 120mm. But I understand they're designed to soak up big hits, and not a bunch of smaller hits like you'd find on an ebike.

I don't know. I'm really lost here. Finding good information about bicycle suspension online means digging through a bunch of peoples opinions about how their forks work for them. Dammit. Why can't bicycle forums be more like the ES where engineers pick apart components objectively!

Auraslip, I was going to suggest a rebuild kit, however - with a little price checking, it is probably less trouble to replace it.

My experience from On The Road: I believe that for the cross-country trek (fully-loaded) the front fork pressure was set between 130-150 psi (and the rear shock between 175-190; each checked every other day). I had both front valves set wide-open for maximum absorbsion, using the air pressure to manage the stiffness, dialing it in till it felt right. When commuting (light load), these numbers HAD to go down, else the bike was too stiff. The opposite is true without sufficient pressure; it will feel odd, flexy, and mushy when braking. At one point in my trek, when I was in SF I had the fork checked out cos I thought that either the fork or the headset bearings were worn out: The guy at American Cyclery instantly wanted me to break down the fork and bring it in for inspection sight-unseen. That was a non-starter (bet he probably thought I fell off the turnip truck), so I made him go out and physically look at my bike and test the load; there is gave-up (mistake on his part) that the headset bearings were fine, although he said my fork needed replacement - hoping I'd spend $1000. Based on how he played with the bike and from the $aucers in his eyes I was able to deduce that the fork was still in good shape, that it was actually holding up pretty well, and with a little bit more pressure it would get me home. :wink:

Lession: Forks are originally stiff when you purcahse them. So long as fluid doesn't leak, just pack more pressure until it stiffens up. Check the headset bearings, or have a pal at a bike shop check them for a second opinion to ensure there is no play. The last thing to check is the torque arms; again - make sure there isn't play. However, I could be wrong; perhaps you've already made these adjustments and it really is time for a new shock

Best, KF

 

[auraslip]

I'm talking about stiffness along the X axis though. Like the fork flexes forward and backwards as if it's stanchions and legs are bending. And this isn't even under braking.


Here is what I want in a fork right now:

Adjustable travel so I can dial in as much travel as possible before handling starts to suffer. Travel needs to go down to at least 100mm.
Through axle
Very stiff. No flexing or swaying while under normal use!
Low maintenance
Can fit a 2.5" MOPED tire in them. (they're usually a bit wider like 2.9")

Stiffness is the most important thing. This is why I want the through axle. An 80lb bike and a 200lb rider jamming on the brakes at 50mph would make lesser forks turn red with strain.

Thinks I don't care about:

Weight
Looks
Price
Tapered steer tube. Do these make a difference anyways?

Anyone know of a fork that meets these qualifications?
I'm looking at a rock shox pike U-turn. They go for around $250 on ebay used. People say they're reliable and a good all around fork..... but are they stiff enough? I don't know.

 

[MadRhino]

You should avoid forks with lock down travel adjusters, they don't last very long, and they often top out when adjusted to lower travel settings. Any kind of locking mechanism makes a fork fragile. Best is adjusting your fork internally, making sure to buy a fork model that can receive travel spacers.

The bigger headsets, 1.5 and conic, along with the bigger stanchion size are made to save weight, for the bigger size tubing can be made thinner with the same stiffness. Yet, they can be fitted with a variable headset for 1.125, that makes for a lot of steer angle adjustment, and that is their greatest advantage IMO. I don't like much the forks with larger size tubing, because I find that it is not a good place to save weight, resulting in stanchions that are easy to scratch and making the fork stiff without the true strength. The best forks for me have 32mm stanchions and 1.125 standard steer tube, but I use long travel DH forks and hit them often, so it might not have the same importance to others.

 

[auraslip]

You should avoid forks with lock down travel adjusters, they don't last very long, and they often top out when adjusted to lower travel settings. Any kind of locking mechanism makes a fork fragile. Best is adjusting your fork internally, making sure to buy a fork model that can receive travel spacers.

So no U-turn or TALAS forks?

I also found this http://www.mtbtandems.com/Forks.html

Forks for tandems! Only the marzocchi forks seem to be mass produced though.

Right now I'm eying a fairly inexpensive DJ2 fork on ebay.

edit:
Another option is FOX forks. They can easily be lowered with a spacer to 100mm.

 

[Kingfish]

Auraslip, if you are up to 50 mph now then you might want to consider another avenue altogether, one that I had considered for a ebike, and that is to acquire a light motorcycle fork assembly with matching crown having the center piece able to mate with your frame. It’s the hybrid solution/best-of-both-worlds. I just fear that 50 mph is reaching beyond the normal scope of DH bicycle forks. My one worry is whether your frame can withstand that sort of consistent wear and tear. :|

As a side, I too desire to go fast, but then there’s a lil’ quirky self-preservation part of a twisted tiny lobe buried in the back of my 2-cell brain that says I’ve pushed the ebike frame about as fast as I care to go without a serious upgrade: I’ve decided to switch to another horse; purpose-built to handle freeway speeds.

Regardless, check out light motorcycle forks; Japanese make some good ones that are adaptable, very sturdy for your use, and safer than a $250 DH fork. In my mind, I’m thinking Kawasaki/Yamaha/Honda 90-250cc range; industry-proven yet not quite full-on heavy motorcycle. Example: ebay Search.

Outside the box, KF

 

[MadRhino]

... I just fear that 50 mph is reaching beyond the normal scope of DH bicycle forks.

Just don't. DH races are seeing faster on rough trails, and pro freeriders drop them 30ft everyday. My Boxxer WC rides better than any heavy MX forks that I had in my life.

 

[auraslip]

hahaha. that's exactly the response I expected from mad rhino. And I agree. if a fork can handle 50 mph while descending a freaking mountain, it can handle anything a road going ebike can throw at it.

That's not to say I haven't looked into other options like you said! http://endless-sphere.com/forums/viewtopic.php?f=2&t=37458
This guy makes adapters to run CR80 fork on a bicycle. Of course they weigh 30lbs and have crazy amounts of travel.

btw I'm ending up with a manitou circus expert. It's a short travel dirt jump fork with air pre-load for around $350.

 

[CORKY]

This is my first post.

I have the same bike Dogman has, a Walmart Mongoose Blackcomb, bought about 6 years ago for $303,
including CA tax.

I'm converting it to front hub drive using a Golden Motor (model 2, I believe).
I've designed safety torque arms for the stock aluminum fork in aluminum 6061 alloy.

I would, though, like to know which STEEL suspension fork Dogman recommends for this, at a very reasonable price
(maybe from a used bike) which would give more safety and at least match the ride of the aluminum fork, which I like ?

I also intend to convert the rear suspension to hard-tail by taking away the spring and bolting the
rocker arms with a 3/8" bolt and spacers underneath the rockers drilling a hole through the frame using the slot in the rocker above the bolt pivot now used.
I will be using a seat post suspension, which I'm sure has more travel than the stock junky rear suspension.

The 12-pound Lipo battery will be mounted cantilevered over the rear tire using a custom designed set of 3 brackets mounted on 3 of the short frame pieces.

Too many subjects here, but I'm mainly interested in the modest priced Steel suspension fork.

Some time ago I had a French racing type bike with very flexible steel fork with smallish ends that you could actually see it flex over bumps. It gave a good ride, even though not a suspension type.

I will be riding only on roads, no off-road trails for me.

 

[Farfle]

I dont think you should upgrade the fork.
Ride that bike to pieces, then buy a quality used bike.
Putting a $500 fork on a $200 wally bike,
is like the kid with a 1990 civic with $3000 rims & $2000 stereo.
Lipstick on a pig.

Enjoy the Genesis as long as it lasts.
Save your money for a higher quality platform.
(With 20" or smaller wheels :wink

Check out my race bike from the 2011 grange race, the genesis frame is a tank

Edit: Doh! Did not see those other two pages

 

[d8veh]

I would, though, like to know which STEEL suspension fork Dogman recommends for this, at a very reasonable price
(maybe from a used bike) which would give more safety and at least match the ride of the aluminum fork, which I like ?


Too many subjects here, but I'm mainly interested in the modest priced Steel suspension fork.

Zoom make a really good tripple clamp steel fork. I can't find a model number of the fork, but they were fitted on this Muddyfox Silverfox Bigfoot. You can sometimes find them on Ebay for next to no money.

 

[CORKY]

Thanks d8veh.
I'll check it out.
Maybe I'll give up the suspension fork altogether and just get a tubular steel one with small ends which flex
for ride quality.
Someone suggested Surly, and I almost bought one on Ebay, but it was ending and I had no time to confirm
it was a fit for the Mongoose Blackcomb.
I should remove the fork and measure and learn all of the specifications; more than meets the eye.

I would wish for a shop with welders and grinders, tube benders etc., so I could really make ideas come to life.
Corky

 

[d8veh]

It's very straightforward to change forks. It normally takes me about 15 minutes. The main thing to check is that the steerer tube is long enough, so measure yours from the bottom of the steering head tube on the frame to the highest point to get the minimum length. A longer one would be OK.

This looks like their latest version 456DH: http://www.hlcorp.com.cn/en/product_show.asp?sendid=1270
or these 621 DH:
http://www.hlcorp.com.cn/en/product_show.asp?sendid=1269
These are steel too:
http://www.hlcorp.com.cn/en/product_show.asp?sendid=1271

Have a look at these. It might give you some ideas:
http://forums.mtbr.com/mongoose-schwinn/post-your-mongoose-64394.html

 

[CORKY]

d8veh, your suggestions are appreciated.

My bicycle days were sometime ago, so the new gear is not fully familiar yet.

Of course my fork is threadless. I am converting my bike to street from mountain style, and want higher
handlebars. Is that as simple as having a longer stem on the fork and adding enough spacers; I'd like about
another 2.5 inches of height ?

Those "Zoom" brand forks look good to me, as I am into mostly smooth roads, although the Los Angeles area
does have lots of lousy roads. We do have many bike paths and more bike lanes.
I assume all of those forks have steel dropouts, as they appear ?
The lighter ones at 5 lbs, rather than 7 lbs. seem better for me.

I am installing a Golden Motor on the front hub, heavy at 15 lbs.

The rear suspension can easily be upgraded by extending the lower aluminum bracket with alloy plates and spacers to virtually any length as it is in the open area
in front of the bottom bracket.

Corky

 

[d8veh]

If you want higher bars, you can use a longer steerer tube and fit spacers. New forks come with long steerers that you normally have to cut down, but if you want high bars, just leave it full length.

All the forks I indicated are steel. They're all relatively cheap. They're not the best suspensionwise, but those on the Muddyfox work well for cheap forks. I don't know about the rest, but probably not as good.

With a1 1/8" threadless steerer, you have loads of choice and easy changeover.