ULTIMATE system?

[HoughMade]

I would urge you to read these before committing to buy:

http://www.motoredbikes.com/showthread.php?t=12798

http://www.motoredbikes.com/showthread.php?t=6529&highlight=black-hat

http://www.motoredbikes.com/showthread.php?t=12796

http://www.motoredbikes.com/showthread.php?t=13991

I'm not saying not to buy, but be aware. I bought from him in the past (as you can see from the last link), but according to these above links, I am in the minority.

Also, be aware of what you are buying- I would never buy the non-adjustable mounting plate because it is a crapshoot with mountain bikes and a no-go for cruisers. Likewise, I personally would not buy the JL Hoot gearbox (looks like an "8" on its side). He advertises the Grubee, but you have to know for sure that is what you are getting.

 

[pmarkwell]

Wow! Thanks for the warning! That Bryan guy seems like a real dirtbag. Sells some good products that I haven't found anywhere else though. I'll need to scour the product forum a little more I suppose. How about bicycle-engines.com? I believe that is also a Grubee setup, is it not?

I used the entire Grubee Skyhawk II kit (with my own engine) which includes a mounting plate.

HoughMade, where did you purchase your kit?

Thanks!

Paul

 

[HoughMade]

Look at the Revolution Cycles review thread- that's where I got it. Like I said, however, I neither recommend for or against (that particular retailer). I only say be careful.

http://www.motoredbikes.com/showthread.php?t=13991

 

[ocscully]

bicycle-engines.com is the retail arm of the US importer of Grubee products BirdDog Industries. BirdDog is the firm that Revolution and other vendors buy from. As to the hub you provided photos of take note that it is a 40 hole tandem hub. You might want to do some searching to see just how readily available 40 hole rims are these days. There are some out there but not very many.

ocscully

 

[pmarkwell]

Ok, so I looked at the Gru Bee website (http://www.grubeeinc.com/) and am I right to assume that it comes with a centrifugal clutch in the gearbox?

I'm guessing that Sick Bike Parts will use the Gru Bee system as well since it's already set up for the GXH50. For the 2 stroke shift kit, why do they run a chain to the downtube, then down to the front sprocket? Is that for stability?

I've already plunked close to $900 for the GEBE and the GXH50 plus clutch and adaptor so I think I'll just go ahead and use that for the time being once my engine comes in. I'm sure I'm not the only one that's interested to see how it will pan out.

If I had the know-how and finances, my dream machine would probably be a GP460 2-stroke on a reinforced bike running a chain driven shift kit. Oh yeah, can't forget the CY NOS kit too . Buy a motorcycle instead, you say. Just dreaming here, folks. I know it wouldn't be safe by any means, but one can dream right?

Paul

Paul

 

[appye]

About putting NOS on your bicycle? No, I think even dreaming about it will blow up your engine. Whaddaya know, I am just about to put together a "GP460 2-stroke on a reinforced bike running a chain driven shift kit" ...

 

[pmarkwell]

Appye, I've been "stalking" your build since I've been reading the thread on the GEBE/GP460 build. You're going to have a manual shift on a dual rear sprocket, right? I think that's brilliant!

Do you think that the GXH50 will be too much for the GEBE too? I guess I'll start with what I have, then if it proves that the Honda motor has too much torque or what-not I'll move to a chain drive like you have with you GP460 .

Paul

 

[appye]

I think it is more of a question of how often and how much riding you will be doing. Like I said, the two main problems with a gebe is belt alignment and ring centering. Don't believe statements about "automatic centering" because of the design. Yes, in a perfect world where spokes don't flex and the ring doesn't slide around (they do and it does) then the thing will stay perfectly centered. The tensioner on a gebe is meant to pivot directly on the surface of a threaded bolt, and does not pivot very well. Using the design from that diagram should ensure (I think, I have not tried it myself) a tensioner design that compensates for out of centered rings pretty well. It also is a good idea to lock the ring down. One user had a pretty good idea for using electrical split bolts to hold the ring in place also. Might want to put a few of those on there. Probably 5-10 ... you don't need to lock every spoke.

Belt alignment is not a huge issue, so long as you don't let your wheel get too out of round. An off center drive ring will probably contribute to tweaking your wheel out of spec. Just make sure that belt isn't rammed against either side of your drive gear and you will probably be okay.

Looking back on it, I am almost tempted to give my GEBE another go round with that nicer pivot, but I am pretty much dead set on getting the absolute most sturdy system I can get ahold of because I want to take it to and from work EVERY DAY. I also want to drive up in the mountains a bit too on the weekends and whatnot.

All this being said, I think that the GEBE belt is plenty strong enough to withstand the stresses put on it by a GP460. Most problems with a GEBE stem from a tweaked or out of round wheel causing uneven stress on the belt. With a chain drive (especially a staton) everything is moved to (and perfectly centered around) the hub, pretty much negating both stress factors.

What do the rest of you think of my assessment?

 

[BigDaddyT]

Nos is pretty innocous. Its the users that get crazy. All nos is 1 part oxygen and 2 parts nitrogen. Air is mostly nitrogen so its a lot like air but air does not have 33% oxygen content whereas nos does. I read somewhere that in a big city air has been tested as low as 8% oxygen content. Where I live I reckon we are 20-24% with good pressure as the vast majority of alaskans live near sea level.
What nos does is allow you to introduce more fuel into the cylinder because you have higher oxygen content than what is availabe in the air. More oxygen + more fuel equals more power. I dont think the small increase in power will justify the expense of installing a kit.
I myself wouldnt be against running nos but im not really building for speed. I just need it to be reliable.