My first race bike build!!!
- Thread starter deonsrace
- Start date
What I'd do here would be to use a good quality sprocket adapter, definitely not the rag joint that comes in our kits, but one like Sportsma Flyer sells, then re drill the sprocket to fit the adapter, or bolt a plate to the adapter that's drilled for these sprockets os they'll be easily interchangeable with your setup. Go almost to the bottom of this page... http://www.sportsmanflyer.com/ Since these are custom made and so are the sprockets, you could probably have them sell you the adapter and instead of the typical sprocket, see if they can cut you one that'll accept the #35 chain, if they can't cut a #35 chain sprocket for you they shold have no problem making you a custom blank sprocket with the 4 holes already drilled where you need them to be.
Awesome!! ... you'll love the performance the CVT offers.. I remember in that go kart I had, everyone thought I was running an 8 to 10hp engine because it accelerated so well... well enough to spin those 8" wide 18" tall tires I was running. It would even do some killer donuts on dry pavement, but it could also spin both tires on a dirt road or trail
I've been looking at finding a way to connect this CVT to the China Girl engines, the drive ratio combined with the right rear sprocket could make for some interesting power and acceleration... http://www.fancyscooters.com/item00478-scooter-part-ninjia-cvt-transmission.html
a 29" will huall a$$ with that setup, just get the right rear sprocket so it'll accelerate hard too... the 212cc engine should get you to about 60mph in fairly close to stock trim and up to about 80 to 90 mph with serious mods... these engines can put out around 20hp with the right parts installed...
I knew I saw another high quality sprocket adapter somewhere else, Jake's also makes something similar... http://shop.jakebike.com/product.sc?productId=125&categoryId=12
I knew I saw another high quality sprocket adapter somewhere else, Jake's also makes something similar... http://shop.jakebike.com/product.sc?productId=125&categoryId=12
That looks great... I'm not so sure how well those radiator clamps will hold up in time or if you do a lot of engine upgrades but these type will be up to the task, and look much much better... http://clampco.com/products/t-bolt.asp You just need to measure your tubing diameter and search the right size for your frame, and you can usually get these on ebay for a really good price, these are the same type clamps used for turbo plumbing and made of stainless so they'll always look great.
Yeah, that alone should push your horsepower closer to 9 or 10 hp... it'll even be stronger with a hot cam and higher compression
I think I was getting around 9hp from that 5hp Tecumseh by using a 21mm carb, removed the governor, and ran it without a head gasket... just sealed it with gasket shellac and let it dry overnight, it never leaked on me but I had the head off probably once a week or more often.
I'd go for the 60 tooth rear and maybe an 8 tooth front for the sprockets, if you can't find a smaller front sprocket, try a 72 tooth in the rear, but usually the front makes a bigger difference, going up or down 1 tooth in the front is like going up or down 4 or 5 teeth in the rear, sometimes the front sprocket is easier to access and change out depending on your setup too.
Yeah... that size may be hard to find let alone finding one that will fit the rear wheel on a bike... that's part of the reason I mentioned changing the front sprocket instead.
Maybe look in Scotto-'s post about his Felt cruisers and see if he has mentioned what size sprockets he's using. That guy has a few really killer Felts built for racing but I hadn't talked to him much or know if he'll help if you send him a pm, he does seem really cool and easy to talk to tho and might be able to help you better with the gearing
Maybe look in Scotto-'s post about his Felt cruisers and see if he has mentioned what size sprockets he's using. That guy has a few really killer Felts built for racing but I hadn't talked to him much or know if he'll help if you send him a pm, he does seem really cool and easy to talk to tho and might be able to help you better with the gearing
Here's some close up pics of his gearing coming off a comet converter... looks like he's running a smaller front sprocket so he can use a smaller rear... this is another effective way to reduce the gearing without running a huge rear sprocket.... http://motorbicycling.com/showthread.php?t=32789&page=14
Looking thru more of his build pages, it looks like he's running a 54 tooth rear but has a double reduction on his jack shaft, and his rear brake rotor is also mounted on the other side of the jackshaft. His bikes crank out over 20hp so you can get an idea how strong the parts need to be to hold up well.
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Yeah... that's another viable option and a good one if you can weld or have someone who can weld for you. I was looking it up on ebay and stumbled on these... These are for Harleys and other custom bikes where space is limited, but one could be made for these bikes using a smaller sprocket and caliper ... http://www.ebay.com/itm/SPROTOR-SUP...005&prg=9311&rk=4&rkt=6&sd=350948575047&rt=nc
Basically it's a sprocket but it doubles as the rear brake rotor and they're used mainly on single sided swing arm bikes or where the builder or customer wants something different. This one of course would be too big and thick for a bicycle, but with a scooter or pocketbike caliper it could be modified and fitted to a #35 or 410/415 size sprocket. This would solve your rear brake problem if you don't want to put the rotor on the jackshaft. You can get away with a much smaller rotor when mounting at the jack shaft because of the gear reduction makes the rear rotor much more effective than if mounted directly to the wheel.
The weld on sprockets would give you a lot of freedom to select the final drive ratio so it's definitely worth looking into as well.
Basically it's a sprocket but it doubles as the rear brake rotor and they're used mainly on single sided swing arm bikes or where the builder or customer wants something different. This one of course would be too big and thick for a bicycle, but with a scooter or pocketbike caliper it could be modified and fitted to a #35 or 410/415 size sprocket. This would solve your rear brake problem if you don't want to put the rotor on the jackshaft. You can get away with a much smaller rotor when mounting at the jack shaft because of the gear reduction makes the rear rotor much more effective than if mounted directly to the wheel.
The weld on sprockets would give you a lot of freedom to select the final drive ratio so it's definitely worth looking into as well.