Bike frames suitable for frame mounted batteries and speed.

[auraslip]

EDIT:

For several reasons this thread is no longer just about Full Suspension bikes. First is that decent FS frames start at $1000. Second is that FS frames with the suspension behind the triangle typically aren't very strong or stable. Third is that full suspension bikes aren't very good for carry racks and cargo, which kinda puts them in the "weekend fun" category rather than the "car replacement" category.

I've started to include frames that can have LARGE 2.5"+ tires in the rear. Because of this I've changed the name of the thread. However feel free to post what ever frames you like.


This is an expansion of the thread I had about soft tail bikes. I've also discovered full suspension bikes with the rear spring/shock behind the frame.

Hey what do you all think about "soft tail" suspension systems?

It seems like it would be simple, light, and cheap.

Obviously not good for trail riding, but the 1 inch of play might be good enough for handling pot holes at +20 mph.

The moots ybb is made of titanium and costs as much as a small car.

The salsa dos niner is only$1000.

The KHS solo one was available as a soft tail in 2005 for $600. Chromoly too. I wish they still made it!

The cheapest I've found is a Schwinn midtown for $300 through costco.

The frame geometry doesn't look good for mounting batteries.

In sumnation scour ebay and craigslist for khs solo one.

It turns out the solo one is a bad choice. It does have disc brake mounts, but no fender eyelets, braze ons for racks, or derailleur hanger.
I would suggest the other bikes on in there 2005 soft tail line up. Especially the police bike. (good luck finding it).

The gt lts-5:

1995-1994 Specialized stumpjumper fsr

What other bikes have the suspension behind the frame? There must be a lot from that period.

 

[Drunkskunk]

The problem with the Salsa and a lot of those shock behind the seat tube is that they have no bottom pivot point.
There was also no pivot point for the seat stays at the dropout, so you eventualy wear them out and they crack.

See? No pivot point on the bottom.

Giant, Kona, Trek, and a few others all make some frames with the shock inside the triangle, but low and to the rear leaving a good deal of room still in the frame.

 

[auraslip]

My understanding of the soft-tail design was that the frame was supposed to flex.

KHS offered a 25 year warranty on all there softtail frames, and in my researching of them I never read of the frame failing at the flex point.

Although maybe I didn't dig that deep.

 

[veloman]

I would like to find a GT LTS, that is the perfect design for an e-full-suspension. I'm currently working on a build with a Specialized FSR from '98, and it's got not inside frame space to put any batteries.

I really want a FS though. I hit this hole in the road today, never saw it, and it jerked me around pretty good. If I was riding a skinny high pressure tire, it would of been a lot worse. The bump popped my bike chain off too.

 

[Mark_A_W]

I'm onto my third full suspension frame for E-bikes, and there is more to it than just frame space (although that is key).


I've broken the swingarm on one bike, a Jamis.


My second, a Kona Dawg, had way too much wobble through the pivot joints (if you whack the bottom bracket area, it wobbles back and forth). And the main swingarm connection to the frame was too light weight for me to dare fitting a rear motor to this frame.


My third dually, the Giant DH team, is solid as a rock, has good space for the batteries..but stock it has a though-hole rear axle. It needed significant mods to fit a hub motor (Kurt did it).


The best stock frame I have seen for an e-bike is a Kona Bass. Removable dropouts (you can make custom hub motor suitable ones), huge swingarm pivot that goes around the bottom bracket.

 

[hurricaniac]

I've found a good used/cheap solution is the Iron Horse Maverick 4.x series. There's decent triangle area (holds six Turnigy 6s 5000mah lipos + connectors), average components, disc brakes and a very heavy duty frame. The only drawback is that it needs a better rear shock, I'd recommend a Fox Float R or better upgrade. You can see my build at http://endless-sphere.com/forums/viewtopic.php?f=6&t=235&start=465.

-Bruce

 

[wasp]

i use a cheap ccm vandal fs with the shock behind the seat
the components are cheap but it was only 150 bucks on sale and all steel
i have 8 lipo's and a lyen 18fet controller in the triangle and still have some room

 

[shinyballs]

Here's some of the better ones...
The Fuji can be had cheap at fleabay.

 

[LI-ghtcycle]

Wow, I just did and image search on google for the GT LTS-5 and was surprised to find this post!

Well, I can't get it so, let me share the love:

GT LTS-5 On Ebay (LOCAL PICK-UP ONLY IN CALI or I'd be all over it!)
http://cgi.ebay.com/GT-LTS-5-/18052...tain_Bikes&hash=item2a07ea1d05#ht_1068wt_1137

They even got a Roxxs Shock on rear replacing the old squish susp.

Hope someone here can snap this up! Starting bid is $150 for the complete bike. Good luck .. and btw ... I HATE YOU (who ever gets this bike instead of me :lol: :lol: :lol: )

 

[auraslip]

Am I missing anything here?

As far as disc brakes go on the vintage GTs go we are out of luck for the rear, but the front fork can be replaced by a newer one with disc tabs.

Does the GT have plenty of screw holes for racks and what not?

I've broken the swingarm on one bike, a Jamis.


My second, a Kona Dawg, had way too much wobble through the pivot joints (if you whack the bottom bracket area, it wobbles back and forth). And the main swingarm connection to the frame was too light weight for me to dare fitting a rear motor to this frame.


My third dually, the Giant DH team, is solid as a rock, has good space for the batteries..but stock it has a though-hole rear axle. It needed significant mods to fit a hub motor (Kurt did it).

Would these problems apply to it?

 

[dogman dan]

I'd buy that GT in a heartbeat for $20. $40 if it didn't need new tires. :wink:

You could hardly go wrong with a specialized frs, though the one I have is too old to have the triangle space in the frame. But one from about 2007 would be good if you can find one at all for sale affordable.

Over on the other end of the spectrum, I couldn't help noticing a Kent brand bike in wallmart the other day. Looks like some of that nice suspension geometry similar to a kona has filtered down to cheap bikes. The shock looks like it would last a week, but hey, it's better than the typical mongoose or pacific in those stores for the last few years. 1 1/8 headset makes the forks upgradeable, and the rear shock should be replaceable too. Good enough for street I'd think, and you could run it stock till you have money for the upgrades.

This isn't the one I saw, but this can be shipped to your nearest walmart. http://www.walmart.com/ip/26-Men-s-Mongoose-XR-200-All-Terrain-Bike/13398155

This is the one I saw in the store. Out of stock right now, but mabye there in the store? http://www.walmart.com/ip/Genesis-26-Men-s-V2100-Dual-Suspension-Bicycle/14089739

And they also have these ones, that look better http://www.walmart.com/ip/Hiland-Tempest-26-Mountain-Bike/14659084 and simiar but more money. http://www.walmart.com/ip/Hiland-Storm-26-Mountain-Bike/14659086


And,,,, not the best for in the frame mounting, but possibly the very best affordable frame to make a high powered rear hub ebike. Tadaa! http://www.walmart.com/ip/26-Men-s-Mongoose-Blackcomb-All-Terrain-Bike/8399258#ProductDetail I didn't know you could still get one of these new.

Honking fat rear steel dropouts on this baby, and mounting lipo to that square frame should be easy as pie. Same frame Dr Bass originally used I think.

 

[auraslip]

My goal is to build a 50 mph almost motor cycle class bike. I want to have as much room in the frame as possible so the battery case doesn't need to extend out, up, and down nearly as much.

I like that even the new wal-mark FS bikes look strongly made. The old GT LTS and Stumpjumpers look like they wouldn't be good bikes to strap 60 lbs of batteries too.

 

[dogman dan]

I guess I missed it, or forgot you were aiming for 50 mph. time to up the donor bike budget to say $3000. To go 60 mph, I just hop on my $700 chinese gas scooter. Insurance and registration are cheap in my state. The cheap bikes may have the same look as a kona, but they will have much much weaker frames. I'm not so sure I'd even want to go 50 on my Specialized, once loaded down with 20 pounds of battery. Weight loaded on bike frames does weird things, you actually see the frame flexing around as you ride. Spooky. But strip off 30 pounds of ebike stuff, and the same bike feels fine going down a hill at 50 mph. So for 50 mph, no to all bikes that originally retailed much under $1500. You need quality tubing, not thin stuff used in cheapies intended for kids to ride on the street.

 

[auraslip]

Hrm........

I guess finding a FS bike that can hold batteries and go real fast is going to be harder than I thought.

 

[dogman dan]

Yeah, it is. 40 mph club is hard enough to get into, but 50 mph club is another story. Don't get my wrong, just about any bike can go 50 mph down a hill. It's just that when you hit potholes and other unexpected road hazards at 50 that the problems start. Then you add enough battery weight and you are compromizing handling enough to get those death wobbles going. Ever experienced a high speed wobble? I have, on bikes, motorcycles etc. Always leaves a brown streak in your pants. Much worse to get it on a bike with a whippy frame.

You might look again at the blackcomb though, it's heavier and stiffer than anything I have ever seen in that price range. That frame was designed for serious DH riding. It's particularly a good bike if you plan on a rear hubmotor with the steel dropouts. As for carrying the battery, you are thinking lipo right? Nothing else is going to be light enough and powerfull enough for 50 mph unless you scrounge som A123's like Dr Bass, who also used a blackcomb for one of his bikes.
On that bike, bolting battery boxes to the frame is pretty easy. You could build something similar to this, on my racing bike. pedal clearance is adequate, given that you won't pedal except for starts. This is a 40mph 82v battery setup of 8 5s turnigy packs (72v), so 8 6s would give you 24s 10 ah, and 100 volts (88v).


I have no doubt the blackcomb is suitable for 40 mph bike with the right tires, and mabye a shock upgrade. You live where you can ride a 50 mph ebike and not have the law take it away? Even where I live, and cops ignore me, I doubt they would if I went flying down the highway at 50. My 40 mph bike will get a few street tests, but mostly will be ridden on a track, or the practice area parking lot.

 

[auraslip]

Hey dogman, I like your battery case. I intend to have a shop make something like that for me.

My inspiration is the fastest electric guy with his 50 mph ebike book. http://endless-sphere.com/forums/viewtopic.php?f=3&t=17301&start=15

He uses a serious Norco DH bike. Alas it is not FS. Even he says the bike can be bad if you hit a serious pot hole at speeds...

Perhaps a bike with the shock in the area by the pedal? Couldn't really extend the case to there any how due to pedal clearance....

As far as batteries....I don't really know. This build will probably take me 6 months to complete. Hopefully a plug and play LIPO option will be developed. If not, I really have no clue on the batteries. Perhaps headway cells, but then you are dealing with the extra weight the cylindrical cells imply.

 

[auraslip]

I've found a good used/cheap solution is the Iron Horse Maverick 4.x series. There's decent triangle area (holds six Turnigy 6s 5000mah lipos + connectors), average components, disc brakes and a very heavy duty frame. The only drawback is that it needs a better rear shock, I'd recommend a Fox Float R or better upgrade.

Also, IH has there recall issues that are not known about b/c each time i tried to have a recall issued. I was ignored, almost lost my job. Here are some of the recalls that should be know about:

IH Maverick Full Suspension frames from 2006-2008 will all break b/c of a weak brace.

IH MKIII 2007 rear swingarms will all crack due to incorrect welding at the factory.



There is no Iron horse warranty on your bikes anymore. The online retailer may be able to break down some bikes to cover this up for a while but they have no pivots kits. They cannot order any frames from the factory anymore.

 

[dogman dan]

Likely won't fit that much of a 50 mph bikes battery into a frame triangle anyway, at least not in such a way that you don't pedal at least a little bit bowlegged.

At 50 of course, pedaling is not happening anyway without gears the size of pizza pans. So pedalability becomes an unimportant item.

BTW, the boxes on my race bike are exactly 6" wide. They are pretty tolerable to pedal around, without any particular bowlegged style. I think even 7" would still be tolerable enough. So the same setup on a blackcomb would work OK.

Lipo will be the only affordable way to get into the 50 mph club.

What you really need to be worrying about, is which bike you can put a 10,000 watt hubmotor on. The limiting factor is going to be how hard it is to make torque plates or pinch dropouts. Again, the blackcomb, or a steel frame hardtail may be the ticket for that. You can weld what you want to it. Not an aluminum frame with alloy rear dropouts.

You realize all this is going to cost $3000 or more right? The 40 mph club is much much cheaper. Definitely under $2000.

 

[auraslip]

I think.........slowly piecing together a $3000 bike is cheaper than a $3000 car. After monthly insurance and gas and maintenance on an older car..

I mean I could buy one of the brammo 60 mph ebikes for $7000, but what fun is that

I can imagine 40mph would be a lot easier. My current set up does 33mph fresh of the charger. Although I have the controller tuned down around 28mph because I don't want to pound to hard on my ping pack.
Truthfully my goal is 45mph for suburban roads, but the traffic goes 50mph on those roads anyways. I might as well keep up.

Likely won't fit that much of a 50 mph bikes battery into a frame triangle anyway, at least not in such a way that you don't pedal at least a little bit bowlegged.

Do you think the pedals could be extended out for clearance? Another thought is that the batteries can be in the frame, beneath the frame, and above the frame.

 

[torker]

Man if I were jumping from 30 to 50 mph. I would consider a dirtbike frame/wheels. But I am not as young and adventurous as I used to be

 

[auraslip]

After researching and thinking about this all day I have decided.
I am going to get a hardtail. Probably a norco because everyone says goods things about them. But really who knows?

Additionally I'm going to reduce my speed aims to 40mph. This is safer AND I can acomplish this with batteries I have now. I will run my four 12v 14ah SLAs in 2s2p for 24v 24ah, and run that in series with my 48v ping pack. I've done the simulations, and even limited to 25amps I should still be able to reach 40mph.

The only problem is that I will be riding around with 70lbs of batteries
Perhaps a 24v 20ah ping booster pack instead.

 

[amberwolf]

All I can tell you based on my much lower speeds but heavy bikes, is that with a hardtail and that kind of battery weight, all on the bike, you're probably gonna break a lot of spokes at 40MPH. Probably destroy rims, too.

That's specifically why I am working on a rear suspension descendant of CrazyBike2. I'm a little tired of wheelbuilding. :lol:

 

[dogman dan]

Get some lipo to series with the ping. Just one 6s 5 ah pack, or two 4s 5 ah pack will get you into the 72-100 volt controllers, and the 40 mph club with out much weight. Then as you have money, add more to extend range, and later on, add more to get rid of the ping. Then carrying the batteries won't be such a problem. the box in my pictures will carry 72v 10 ah. Wtih light batteries, the hardtail should work, just watch the potholes and curbs.

 

[auraslip]

I use my bike every day dogman. Sometimes when I'm mowing someones lawn I'll plug in to charge my ping pack. It takes all of a minute to run the extension cord and plug in and to unplug when I'm done. With LIPO I understand the procedure is much more complicated.

Instead of my sla pack, perhaps a 24v ~10ah booster pack of some other sort of chemistry. I can switch it on when I need to go 30+ mph. Ebike.ca has 24v 8ah nicad packs for $175.....
I really wish ping was more than 1c....24v10ah is 5lbs and $250 shipped..

 

[StudEbiker]

I haven't been following this thread, but based on the topic heading I thought I would post this. I saw one of these today and was drooling over the triangle space. Another bonus is that the down tube is flat on the top and at least two inches wide. And it comes standard with a front disc.

http://www.coolbiking.com/brands/mongoose/mongoose-vanish-26-inch-dual-suspension-mountain-bike/