I've purchased a couple 4g kits from bicycle-engines.com and they were the tapered shaft engines. The clutches that came with these kits had an engagement rpm that worked fine. The last 4g kit they shipped me had the engine with the 5/8 shaft. The clutch in this kit wants to engage when I pull the recoil starter. I installed stiffer springs in the clutch because I had success doing this with these clutches in the past. Didn't work this time. I installed some shims with the stiffer springs and now I can start the engine without the clutch engaging, but it tries to engage at idle. I set the idle as low as it will go without stalling the engine and the clutch is on the border of engaging. Anyone else buy the 4g from bicycle-engines.com with the 5/8 shaft engine? I have one more 4g kit with the tapered shaft engine and I was thinking about putting it in this bike just so I can have a clutch that works properly.
4g kit with 5/8 shaft engine
- Thread starter agk
- Start date
scotto-
Custom 4-Stroke Bike Builder
My only suggestion besides using the tapered shaft engine with the 3-shoe clutch on the 4G would be to get an EZM tranny for the straight shaft HS engine and sell the 4G tranny with the whimpy clutch. Or send it back in exchange for a tapered shaft HS (if they have any). Sorry to here this, good luck.
agk,
The problem you are experiencing is two fold. The springs are part of the problem and the other area is the Bronze/Oilite Bushing. If you don't keep this bushing lubed it can cause enough drag to stall the motor at idle, or cause the bike to take off like a jackrabbit when starting. There is a USA made Oilite bushing that you can purchase from McMaster Carr that some members have had success using to replace the stock Chinese bushing. I've bought some of these but have not used them yet. I carry a small plastic bottle with a mixture of 30wt. motor oil and 20% Marvel Mystery Oil and add a drop to the bushing at the end of the crankshaft when it starts to drag. Link to replacement bushing McMaster-Carr Down at the bottom of the page Part# 6659K33 is the bushing that others have used and are claiming works much better than the stock one. Things to be aware of with this bushing is that it is not an exact size replacment. Though as I said above other members have reported success using them. They are very inexpensive to buy $1.39 each, so it hardly seems like you could go wrong giving them a try?
ocscully
The problem you are experiencing is two fold. The springs are part of the problem and the other area is the Bronze/Oilite Bushing. If you don't keep this bushing lubed it can cause enough drag to stall the motor at idle, or cause the bike to take off like a jackrabbit when starting. There is a USA made Oilite bushing that you can purchase from McMaster Carr that some members have had success using to replace the stock Chinese bushing. I've bought some of these but have not used them yet. I carry a small plastic bottle with a mixture of 30wt. motor oil and 20% Marvel Mystery Oil and add a drop to the bushing at the end of the crankshaft when it starts to drag. Link to replacement bushing McMaster-Carr Down at the bottom of the page Part# 6659K33 is the bushing that others have used and are claiming works much better than the stock one. Things to be aware of with this bushing is that it is not an exact size replacment. Though as I said above other members have reported success using them. They are very inexpensive to buy $1.39 each, so it hardly seems like you could go wrong giving them a try?
ocscully
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That's me. If you are familiar with our website you will find some performance parts on there in the near future for the 49cc HS engine and the 79cc HF.
Quenton Guenther
Dealer
Hi agk,
Please list your website, so that we can have access to the parts your are developing for the 4-stroke motors in the future.
Have fun,
Please list your website, so that we can have access to the parts your are developing for the 4-stroke motors in the future.
Have fun,
Quenton Guenther
Dealer
Their address is Affordable Go Karts - Home page - AGK - http://www.affordablegokarts.com A lot of information about 4 stroke motors.
Have fun,
Have fun,
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scotto-
Custom 4-Stroke Bike Builder
We will be focused on engine performance parts for the 49cc HS and the 79cc HF. It's a long process to develop parts, test them, tweak them, test again and put into production. We are working on it and having some fun at the same time. We'll post the new products on the forum as they become available.
