need help...Tanaka 47R

Looking for a clutch cup assy with shaft. I'm new and just starting a build. Do the china bike gearcases have a 78mm clutch cup? I have one available to me. I don't really want to buy a whole kit and I think this motor will rip a GEBE setup to shreds! Any suggestions?

 

Staton-inc used to sell kits with the 47r. I would rifle off an email to them to see if they have a gearbox setup that will fit it still. I wish they still made them I've heard they are mighty powerful.

 

i swear, i'm not trying to sell (no need ) but merely inform...in case you haven't seen this project: http://www.motoredbikes.com/showthread.php?t=11738

and if yer not already aware of "davesmotors", there's a link to them in that GP460 topic, bet ya could find some drive components there

 

Gebe needs to make a high torque version of their setup using one of those thick timing belts and a mag wheel with the spoke ring affixed and pre-centered. If I were them I'd be all over that r+d. Using automotive belts would give the benefit of being able to go into an auto store and ask for a timing belt rather than ordering one. I recently helped my paps replace his timing belt on his nissan frontier, **** thing lasted 130k miles before it finally de-laminated itself. Of course efficiency would drop with the larger belt but if you could use larger engines with the gebe kit it would totally haul being so lightweight.

 

Good idea SirJakesus. One thought about that though is why would they want to de-prioritize their belt? I would think the profit margin on those belts must be pretty high. I think the mag wheel is an AWESOME suggestion...that seems (to me) to be the weakest link in many of these kits.

Warner

 

I agree, GEBE would do well to r&d a wider belt for the larger Tanakas; granted it would be a lot more expensive but some folks would be all over it, I'm sure!

 

The belt GEBE uses might work better if the drive sprocket was larger in diameter (more teeth to distribute the load to) but that would alter the gearing. A wider belt would not track as easily and a thicker belt wouldn't bend around as tight a radius. IMHO, a small primary gear reduction box bolted to the clutch PTO would be a plus and then you could go to a heavier belt with larger drive sprocket. I'd guess that there is a good amount of engine bracket flexing during normal use and a high HP setup will compount this problem. Bracket flexing will loosen the belt and cause it to twist and not track as intended. I've used this type of toothed belt on industrial drill motor setups with no problems for millions of cycles, but again, these machines are very ridgit in design.
I'm kinda surprised a primary chain setup would hold up any better than a belt system. Roller chains don't take well to open air high speed use. They require lots of lubrication and that would be impossible on a bicycle.

 

I'm not sure I understand your logic regarding chains. Motorcycle and bicycle chains both seem to hold up for great lengths of time, and although they need PROPER lubrication, I don't think that equates to "lots" or "frequent" lubrication. Just my thoughts. I don't think it's the belt that is the weak link in the GEBE system though....I still think it's the wacky looking ring that attaches to your spokes, as opposed to a normal sprocket and hub like the Staton kit uses. Just my opinion, of course.

Warner

 

yup, only opinion, all about the fun...here's mine

well, let's look at this geometrically. again, i don't need to bump sales, this is about the fun of "bench-racing"...

i don't care where you drive the wheel from...ultimately, it comes down to stressing each individual spoke at a single point, right? well, think about it...properly installed, the gebe drivering actually exerts the (motorized) stress at a point that is more "wheel-friendly" than any hub-based drive can possibly be...by moving the point of stress closer to the rim, you've reduced the overall stress to the whole wheel assembly. the drivering fits the spoke arrangement very precisely, and serves to hold the spokes in their proper position better than a hub or sprocket can. it's mechanical logic.

and, because we're talking about weight and power ranges that are significantly smaller than any other vehicle, belt-drive makes sense. imo, any wheel that the gebe system would break wouldn't stand a chance being hub-driven.

 

Okay...first let me state that I think the GEBE and Staton systems are the two best that I have found. I'd be happy with either of them. I've stated before that the show-stopper for ME was that the GEBE system doesn't truly freewheel and the Staton system does. That was imperative to me, personally. Many people won't pedal as much as I intend to though and that won't be a factor at all. Beyond that, here are my thoughts in regards to your comments:

I disagree. I'm not an engineer, but if I'm not mistaken, the GEBE drive ring does not use ALL of the spokes to drive the wheel, correct? And the Staton system (just like a bicycle or motorcycle) shares the load between ALL of the spokes, by virtue of driving the hub itself which all of the spokes attach to. Unless someone can prove to me scientifically that it's not true, I refuse to belive that the GEBE system is more robust or puts LESS stress on the wheel and/or spokes than the Staton system.

I don't doubt the strength of the belt itself at all. Harley Davidson uses a belt drive system on many of the big torque v-twins and it's quieter, smoother, lighter, and more efficient (only by about 1% max) than a chain drive system. In fact, you'd probably see this on more motorcycles if Harley didn't own most of the relevant patents on the system. I'm not against the belt drive aspect of the system at all. I just don't like the drive ring attaching to the spokes. I don't believe that it's stronger than the Staton system. An easy test would be for someone to simply pedal two identical bikes with identical rim setups as far as the gauge of the spokes and same wheels, etc...one with the Staton hub and one with the GEBE ring (but you'd have to hook the pedal sprocket up to the GEBE ring on the spokes somehow). While pedaling, shock each one by jumping on the pedals over and over and see which one failed first. You can do this on a nomal bicycle (with the hub driven setup) all day long with no ill-effects. Can you do this with the GEBE ring attached to the spokes? Not on one that *I* paid for, thanks. Again, maybe I'm way off base on this, but those are my thoughts about the comparison between the two systems. I have ZERO vested interest in either kit....these are just my opinions.


Warner

 

mathematically correct, but geometrically?

ah-ha! but look at where the spokes are stressed. it truly makes a difference...it's about leverage. under motor-power, it's about putting rubber to the road...the golden eagle ring gets much closer to the road (rim) than a chain & sprocket. easily more than twice as close, if that makes "mathematical" sense. same wheel, same horsepower, within legal motorized bicyle limits...i have to say i think the belt & ring would prevail.

maybe a whizzer dood could chime in about why the sheave-setup has survived so long.

and, please don't misconstrue...just like you, i'm just gabbin'...everything i hear about the staton drive says heavy-duty, and everything i hear about the staton company says reliable. there's plenty to go around for companies that deserve the business.

and they use epa-certified engines, good enuff for me

and, let's be clear...if everyone would build a bike with wheels that were mechanically suited to this stuff, the topic would be moot anyway

 

peddler,
i was shocked by augidog linking to my build thread in yours in support of the GEBE drive system. at the time i was having real problems( ALL realitive to my asembly ) and was considering going to chain to be done with it.

well, things have changed. with help from the many memebers of this forum i have found and remedied all the problems i'd created or was unaware of in the assembly of the GEBE drive and my build is now fully functional and very satisfying.

i'm running a GP460, 4.5HP/ 2.3 TRQ engine with NO problems realitive to the GEBE drive or belt. i fouled a plug last night due to my own neglect though

the point is, IMHO the Tanaka 47R is well within the abilities of the GEBE drive and belt.

member kawasaki999 has both engines mentioned here running the GEBE system, you should shoot him a PM and get his take. he's a real friendly guy and knows alot about these 2 strokes in general.

thanks,
steve

p.s. i agree with augidog about the whole wheel / spoke issue, when the bike is built with purpose specific parts it puts an end to these concerns and issues.

 

I'm sure that properly built, the GEBE system doesn't have spoke issues. And when I talked to Staton and told him that my tires are only 1 1/4" wide, he said he would STRONGLY recommend getting a 48 spoke 1" wheel from him when I order my kit, which I would do of course. It's only about $70 for the wheel, ready to go so how can you beat that? Like I said, either system would work. I just REALLY want the true freewheeling of the Staton system and also (just my opinion) don't like the looks of that big drive ring on the spokes. But if Staton went out of business I wouldn't hesitate for a second in knowing what my other option was. After Staton and GEBE, it gets VERY sketchy for me. I might at that point try to make my own system using one of the good engines like Staton and GEBE use.

Warner

 

we cool, buddy

man...ain't this grand fun?

 

Peace. Hehe...

Warner

 

Warner,
I didn't explain myself properly in regards to chain drive. Chain drive right off the crankshaft/clutch is a high maintenance choice. In part, this is due to a lack of proper lubrication (bath type and or pipe feed oil), a minimum drive sprocket size of 17 teeth which would upset overall ratio reduction, and a minimum of 120° arc contact. People refer to motorcycle primary reduction systems and use these as comparison, they however are designed properly (in most cases) and usually don't see more than a 3.0 reduction ratio (7.0 is suggested as maximum). Staton, for example, uses a geared primary reduction box, which allows them to successfully follow up with a "secondary" reduction chain drive to the rear wheel.

Here's a good website regarding chain drives:
http://mechanical-design-handbook.blogspot.com/2007/09/standard-roller-chain-drive-design.html

 

Makes sense. And you're correct....most motorcycles are 3:1 or less. And as you mentioned, the Staton system is engineered correctly for chain use.

Thanks for clarifying,

Warner