Project 29er With Twin CY460 Engines!

[lowracer]

5-7,
I'm looking forward to seeing this project come to fruition as I've enjoyed your previous work...
-Lowracer-

 

[5-7HEAVEN]

Hey thanks a lot, man.

I can't believe the local bike shop has been sitting on my new frame for 11 months!

 

[sparky]

If the clutch is the only beef you have the with the GP460, then get the better clutch springs that you'll HAVE to get a month or so down the road. Just replace the springs up front!! I'm just not a fan of the twin motor idea, but to each their own.

29'er + 47R + shift kit + Nuvinci hub = "the ultimate"

I guarantee you that such a build would beat any Thing else. PERIOD.

In terms of acceleration [up hills], top speed, weight, balance, etc.

It seems that the shift kit is the only way for the Nuvinci to freewheel without the Staton gearbox. Staton gearbox is just too heavy for me.

But yea... it sounds like you've already got it all set up, you just haven't put the wheel on the bike. Try that out for me and let me know how awesome it is!!

 

[lowracer]

I have often thought about installing a 2nd engine on my bike (I even went as far as buying some specialty connectors to attach a rear rack to the axle) but I never went through with it. Having recently changed from a heavy Lifan 98cc 2.5 to a light Pocketbike engine I can see that the biggest obstacle is weight. Keeping things simple (my philosophy) has kept me from tackling this project but I still think it would be awesome having that much extra power throughout the rpm range I ride within, even for just a little while as an experiment. The bike I ride now has more than enough power for speedy acceleration & speeds up to ~50mph+, but it sure would be fun pulling both throttles...
Cant wait to see how your project come out....DragonLady was quite the machine...(great vid)
-Lowracer-

 

[5-7HEAVEN]

If the clutch is the only beef you have the with the GP460, then get the better clutch springs that you'll HAVE to get a month or so down the road. Just replace the springs up front!! I'm just not a fan of the twin motor idea, but to each their own.

29'er + 47R + shift kit + Nuvinci hub = "the ultimate"

I guarantee you that such a build would beat any Thing else. PERIOD.

In terms of acceleration [up hills], top speed, weight, balance, etc.

It seems that the shift kit is the only way for the Nuvinci to freewheel without the Staton gearbox. Staton gearbox is just too heavy for me.

But yea... it sounds like you've already got it all set up, you just haven't put the wheel on the bike. Try that out for me and let me know how awesome it is!!

I have tried various aftermarket clutch springs on the 460 engine. I also replaced the its clutch with a velvet-smooth pocketbike clutch.

They all failed within a few months.

Granted, it could've been because of the steep learning curve of using this engine. It could've also have been because I expected the engine to pull away from a standing start. It could've been because of using a 32t first gear, instead of a 34t. This engine's clutch springs failed with friction drive AND shift kit.

On my last clutch spring failure in its center-mount position and shift kit, I decided to pull the 460, replacing it with a new Tanaka 47R engine. It was a good choice. Even though the 47R might have less power, it gets the job done on my commute. In its center-mount position, its expansion pipe wraps perfectly around the top tube. In eight months running, the Tanaka has not experienced any clutch issues or ANY problems whatsoever. The 47R is considered a loud engine, but it's much quieter with a pipe. It also gets about 80mpg, accelerates very well and cruises easily @ 35mph. If pushed, it will maintain 40mph and peak past 45mph. AND, it is a very dependable engine.

IMO, Tanaka 47R is the BEST high-performance engine for use with a shift kit and cassette gearing. It would work well with a 26" OR a 29er. Cassette gears should be a better choice than the NV hub. They are more than 10 times cheaper, MUCH lighter and easy to replace. In a center-mount position, the bike is better balanced than a rear-mount setup, ESPECIALLY if fitted w/a cassette. With an NV hub, it becomes tail-heavy, I would imagine.

Staton gearbox isn't really that heavy. Engine power nullifies extra weight. My Trek w/Mits TLE 143 engine, Staton box and NV hub weighs 62lbs., the same as my Diamondback bike w/center-mount Tanaka engine. The Trek's front end is EXTREMELY light; the Diamondback is almost perfectly balanced w/its 29" ROCKSHOX fork. Methinks that extra weight needs to be added to the Trek's front end. It seems too easy to jerk the front end off the ground and flip over backwards.

As mentioned before, I have two 29er frames. One will run twin 460's, just for the heck of it. The other will run a spare 47R with shift kit and 11t-34t cassette. for the 29er w/shift kit, I'm trying to get a vendor to fab an 80-tooth 8mm chainring sprocket. This would lower first gear from 37.09:1 to 41.2:1 to compensate for the taller 29" tires. Eighth gear would be more usable @ 13.33:1, instead of 12:1.

I wish I could center-mount the Staton twin-engine gearbox. The bike would be better balanced than a rear-engine setup. With too much weight on the tail end, I just might HAVE to center-mount the twin-460's.

 

[5-7HEAVEN]

I have often thought about installing a 2nd engine on my bike (I even went as far as buying some specialty connectors to attach a rear rack to the axle) but I never went through with it. Having recently changed from a heavy Lifan 98cc 2.5 to a light Pocketbike engine I can see that the biggest obstacle is weight. Keeping things simple (my philosophy) has kept me from tackling this project but I still think it would be awesome having that much extra power throughout the rpm range I ride within, even for just a little while as an experiment. The bike I ride now has more than enough power for speedy acceleration & speeds up to ~50mph+, but it sure would be fun pulling both throttles...
Cant wait to see how your project come out....DragonLady was quite the machine...(great vid)
-Lowracer-

Yeah, I miss the Dragon Lady. That bike could run WOT for 10 miles in 87* weather without missing a beat. It was a heavyweight @ 105 lbs, compared to my faster 62lb Diamondback. If I had a garage, I would've kept that twin-engined bike. Friction drive ate tires regularly; I would've replaced both drives w/BMP chain drive.

In contrast, I expect Project 29er w/twin 460's to weigh around 70lbs.

Yes, it was a BLAST! pulling two throttles! The engines DRONED instead of screamed. There was MUCH less stress on each engine, because they were sharing the load.

I expect the same to happen with twin 460's.

 

[Deleted Member 4613]

My reaction, excellence in engineering is simplicity. Rather than two motors, two drives, one more powerful engine makes sense in terms of complexity and weight. Keep your designs as simple as possible.

 

[5-7HEAVEN]

Simplicity is finding a powerful DEPENDABLE engine with a RELIABLE 76mm clutch. An early-model Staton gearbox or his twin-engine box do NOT have external access to the engine(s)' motor mount bolts. To simply replace a clutch spring would require considerable effort, not something to be tackled on the roadside. The gearbox would have to be removed and the case split. With the Scooterguy setup, simply remove four engine mounting bolts, carb connection and killswitch. The engine then falls away from the bike.

The 460 engine is an affordable, powerful engine. However, its clutch leaves something to be desired. If I could adapt a Tanaka 47R clutch to it, I'd consider using it as a single engine bolted onto a Staton box.

Since I don't consider it a reliable engine, a spare engine would be insurance of roadside failure.

Besides, I've got the twin-engine gearbox, so I might as well use it.

Also, where else will you find 8.5hp for $500, which will bolt onto the 76mm drive systems?

FWIW, I ran a twin-Mitsubishi engine/friction drive setup on my Raleigh cruiser. It was simple and powerful, but a heavyweight at 105lbs.

 

[5-7HEAVEN]

My reaction, excellence in engineering is simplicity. Rather than two motors, two drives, one more powerful engine makes sense in terms of complexity and weight. Keep your designs as simple as possible.

Staton gearbox uses two motors and a single chain drive.


Twin-engine box weighs a few ounces more than his regular chain-drive. The extra 460 engine weighs less than seven pounds. Total weight of both engine is 13lbs. Honda GX50 has the size/weight of two 460engines.

 

[Deleted Member 4613]

Well good luck with the two engine concept, but I don't think two engines would make it in any market, except for an aircaft..