New 26" Fat Bike
- Thread starter huffy80
- Start date
I've seen those... they're nice but with that small frame things would be really tight with a China Doll engine, but since it's a steel frame, you could cut out the top tube and weld in a curved one or 2 straight tubes side by side just far enough apart for the top of the jug to peak thru... I've seen someone in here do that on a 20" BMX so the engine would fit in the frame and it came out looking great.
You can get a China Doll in there but it definitely takes some modifying and if your a big guy it will make your look like a monkey on a football! I don't know why the didn't stretch them frames a little further! I just watched this video earlier today and look how he had to mount the engine, its offset over to one side........
http://www.youtube.com/watch?v=okr3m3LY9N4
http://www.youtube.com/watch?v=okr3m3LY9N4
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The side mount is a good idea on these not only due to the frame space limitations but also for sprocket alignment... there are some things that should have been done differently but he had the right idea.
What I would have done differently was for one, not drill thrum the seat post tube and run a bolt thru, this not olny weakens the frame but also there's no way that bolt will stay tight on its own, the tube will crush a little, the vibration will wallow out the hole, then it gets re tightened, repeatedly until that tube fails.
the fix here would have been to weld the plate to the seat post tube and the top frame tube, this would make the frame considerably stronger and nothing can work loose. Another alternative if a hole must be drilled would be to drill the hole oversized on one side then installnanspacer thrum the tube so there's somethine solid to tighten the nut against.
the front mount is an exhaust clamp holding a steel plate that the engine is bolted directly to... again, vibration can make that clampnsaw thru the tube fairly quickly,especially with a side load... using a section of tubing the next size up for the clamp to ride on spreads the load more evenly so it'll last longer, welding the plate and using gussets or a second plate forming a triangle would be far stronger and wont fail.
Otherwise this is an excellent build and the side mount method will work for this setup. There were some things I saw that could have been done different but with that, there are solutions both with and without the need to weld. If this bike is a daily rider things should be done to keep it safe, but if its only ridden occasionally like putting around at a biker rally or other event it'll last just fine.... very nice build in my opinion
What I would have done differently was for one, not drill thrum the seat post tube and run a bolt thru, this not olny weakens the frame but also there's no way that bolt will stay tight on its own, the tube will crush a little, the vibration will wallow out the hole, then it gets re tightened, repeatedly until that tube fails.
the fix here would have been to weld the plate to the seat post tube and the top frame tube, this would make the frame considerably stronger and nothing can work loose. Another alternative if a hole must be drilled would be to drill the hole oversized on one side then installnanspacer thrum the tube so there's somethine solid to tighten the nut against.
the front mount is an exhaust clamp holding a steel plate that the engine is bolted directly to... again, vibration can make that clampnsaw thru the tube fairly quickly,especially with a side load... using a section of tubing the next size up for the clamp to ride on spreads the load more evenly so it'll last longer, welding the plate and using gussets or a second plate forming a triangle would be far stronger and wont fail.
Otherwise this is an excellent build and the side mount method will work for this setup. There were some things I saw that could have been done different but with that, there are solutions both with and without the need to weld. If this bike is a daily rider things should be done to keep it safe, but if its only ridden occasionally like putting around at a biker rally or other event it'll last just fine.... very nice build in my opinion
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I was thinking maybe I could fit a 212cc motor in it like this guy did:
https://www.youtube.com/watch?v=CzEgWnnBMcs
https://www.youtube.com/watch?v=CzEgWnnBMcs
Awesome! 212 ain't enuff! LOL
I'm pretty sure the lack of space is the main reason these don't get built often. There's also the chain alignment issue of course.
Note: it is not ok to use an engine as structure for your frame. This will likely work for a while, but then it'll be bad news.
I've looked into building one of these, and have considered having the frame modified by a GOOD welder.
Maybe a drop loop, like a Worksman Flyer frame? While that's happening, you could add mount points for an engine...
There's lot's of options, keep us informed on your progress, and good luck!
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You can put an electric motor on it.
Pricey but exceedingly cool.
1.7 KW motor, 960W 48V LI battery, and it uses the bikes gears.
Wedging a 2-stroke in there will a be a chore, but if you try I suggest you use a sick bikes jackshaft and keep your engine centered in the frame.
This transfers engine power to the right and ties it into the pedal system like that electric.
No chain clearance issues, you can keep the rear disc, and your motor is now a 7-speed shifter ;-}
Pricey but exceedingly cool.
1.7 KW motor, 960W 48V LI battery, and it uses the bikes gears.
Wedging a 2-stroke in there will a be a chore, but if you try I suggest you use a sick bikes jackshaft and keep your engine centered in the frame.
This transfers engine power to the right and ties it into the pedal system like that electric.
No chain clearance issues, you can keep the rear disc, and your motor is now a 7-speed shifter ;-}
Looks great! I'm not finding that kit on their website:
http://em3ev.com/store/index.php?route=common/home
Did you buy it there?
http://em3ev.com/store/index.php?route=common/home
Did you buy it there?
You can put an electric motor on it.
Pricey but exceedingly cool.
1.7 KW motor, 960W 48V LI battery, and it uses the bikes gears.
Wedging a 2-stroke in there will a be a chore, but if you try I suggest you use a sick bikes jackshaft and keep your engine centered in the frame.
This transfers engine power to the right and ties it into the pedal system like that electric.
No chain clearance issues, you can keep the rear disc, and your motor is now a 7-speed shifter ;-}
I just bought the triangle shaped battery and charger from Paul at EM3ev, they make some battery packs with a really good BMS built in.
The rub is they are in Japan and it is damn expensive to ship.
From what I understand there is pack maker in Florida which would save a ton but they never got back to me so....
This is the electric shift kit I used.
http://www.sickbikeparts.com/catalo...ucts_id=181&osCsid=isn8122p21bvpbqqav8j5kgl44
You might want to consider a bigger controller, we got a little crazy with this build and toasted the Kelly KBS48 101L-L controller pushing it to it's limits climbing steep mountain trails in 105F temps.
A more pressing issue is the BB motor mount, it is designed for standard BB width and this bike has a much MUCH wider one.
This is my build topic on it for tips.
http://kcsbikes.com/topic.asp?TOPIC_ID=734
Like I said, pricey, but so frigg'n cool and quite everyone loves it ;-}
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Pretty cool, a pair of electric hub motors.
No gears like mine but still cool with 2-wheel drive.
That is no 10KW besat though, maybe those hub motors are capable of handling 5KW each but that battery pack isn't putting out anywhere near that.
The motor I use is capable of nearly 2KW but my nice pack doesn't even quite put out 1KW, but with gears it'll outrun that direct drive until you hit a hill that needs 2 wheels turning to climb it.
Storm is supposed to launch in the next couple of hours. Signing up on their face book is supposed to get you in on the introductory price of $500.
http://comingsoon-tech.com/storm-ebike
http://comingsoon-tech.com/storm-ebike
What a great show of garage mechanics coming up with something they can produce with common easily replaceable parts.
Really, hats off to those guys!
They took this $200 bike, laced in an eHub, based the battery on the common 'water bottle' battery and mount, then made a killer swing hatch metal 'box' to incase it via the batter mount!
No muss, no fuss cable and wiring...
Overall a really fine job, especially the nice rounded edges and overall smoothness of their enclosure.
I'll snag one for $700 with shipping, the parts are worth that, and it might be fun to compare to mine in a video ;-}
Really, hats off to those guys!
They took this $200 bike, laced in an eHub, based the battery on the common 'water bottle' battery and mount, then made a killer swing hatch metal 'box' to incase it via the batter mount!
No muss, no fuss cable and wiring...
Overall a really fine job, especially the nice rounded edges and overall smoothness of their enclosure.
I'll snag one for $700 with shipping, the parts are worth that, and it might be fun to compare to mine in a video ;-}
I'm sure with 350w it's not fast, but 20 mph is fine for a ridged frame. The Battery is 36v 10ah which should be good for 20 to 30 miles. That's comparable to most factory eBikes that cost twice as much. My son has 350w Neo Carbon eBike, and it's plenty fast up to 25 mph so this bike shouldn't be to bad for a lightweight rider, like my wife for instance.
I'm in. Even if I don't like it I'll sell it for cost.
I'm in. Even if I don't like it I'll sell it for cost.
I'm familiar with the batteries, I have a brand new one here I'm mounting as a replacement for a different type on a prior build from 3 years ago.
The speed bottleneck is the motor, 350W max and rpm max.
Anyway, they are not the carefree easy to ride toy the pics look like...
The nearly vertical rake, short wheelbase, and big heavy front wheel makes it darn cumbersome to control, especially at low speeds.
Looks like you can buy on their web by the 9th, next round price increase will be $100.
Regardless May delivery if everything runs smooth.
I'm fine with that, it will help the guys stay liquid and move product until they can finally sell them for a profit.
And like you, I can always move it on as well.
Did you buy one? 
Did you get the extra battery for $180?
$88,420USD RAISED OF $75,000 GOAL
They did not email me on 2 addresses......
Did you get the extra battery for $180?
$88,420USD RAISED OF $75,000 GOAL
They did not email me on 2 addresses......
$500 + shipping ( lets say $650?) is not bad even for a wimpy 350w @ 36v. You just have to wait 3 or 4 months to get it that's all. Gonna be a looong wait for you guys. They say it has 29x4.6 tires and hydraulic disc brakes. wow. alas, its not what I need. What I need is a good battery pack for my Schwinn.
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