Honda gx25 questions

You can probably friction mount it over the rear wheel with a kit from THATSDAX or STATON.

The Honda gx25 has a 52mm clutch. The thatsdax.com friction drive kit won't work for you because their kits are for 76mm clutches only.

Staton.com does offer a friction drive kit that you can use a Honda gx25 with. When you order a kit from him, you specify the size clutch drum you want as well as the roller size. For a Honda gx25 you will probably want a 7/8" roller - unless you only intend to ride on flat ground and/or you are very light - in which case you might be able to use a 1" roller.

Staton makes excellent products, but his instructions are a bit sparse and leave a lot of details up to the installer. Staton is very willing to give you advice as to what you need, but I would suggest calling rather than emailing as he doesn't get around to answering emails very well.

The Honda gx25 is only rated at 1.0 hp. It is a very usable, quiet and reliable engine for a motorized bicycle, but its power is on the low side.

jaywood said:

Is there any way I could go belt/chain driven?

Thanks for the quick responses guys!

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You didn't mention budget but yes, GEBE makes a neat, belt drive that readily bolts right up to the Honda 25. I knew one guy who first had the 35 and then downsized to the 25 because it suited his needs better. He lived in a SoCal beach town, houses close together, and quiet was important for him.

yes noise is a problem. my son showed me the southpark episode about the harley riders making noise. so funny and true

jaywood said:

Anyone? Suggestions?

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I have the GX35 on a beach cruiser and it's quickly become my favorite commuter bike. I have it mounted with the GEBE kit it is the most efficient way to go. With that small Of a displacement you will definately want efficiency. I personally will never go back to friction drive but it's upto you. To each his own.

jaywood said:

This is a budget build...otherwise I would like the gebe kit

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Well there you go sounds like you have your answer. Good luck and keep us posted on the build.

The clutch drum you have is an OEM product made to fit piece of lawn equipment, or something similar. They usually have a housing with bearings (hence the C clip) and a flex or solid shaft with a square end that drives the equipment. The various bike kits mentioned above in the thread would mean one wouldn't need that drum because the kits come with their own and the whole things just bolts together.

If you want to go DIY, you need to build some kind of mount that attaches/bolts to the bike and then bolt the engine to that with the 4 threaded engine mount holes. How you design that mount will determine in large part what kind of drive spindle you can go with. The simplest is direct drive which would mean attach the drive spindle to the flywheel without a clutch or drum. That means the spindle is turning all the time the engine is running IE direct friction drive and when you stop you either kill the engine or build a manual clutch to lift it off the tire.

If you want to use the centri clutch, you would need to develop some kind of bearing support or housing that would hold the bearings and shaft and attach the drive spindle to the stub on the clutch drum you have. Probably the simplest way to do that probably would be to weld it.

There is more than one way to skin a cat and DIY means you have to do it yourself. I would suggest you read up on the threads by members Deacon and Cannonball2 here. Both have come up with numerous ways to build homemade friction drive bicycles.