I have a 3.5hp side pop exhaust with a new ebay carb, new max torque 10 tooth clutch, and a 72 tooth rear sorocket on Manco Thunderbird. I believe i have the carb adjusted properly. The issue is the take off acceleration which is SLOW. It gets up to speed and rides well. On grass its even much worse. Like you can walk with it. I hear people talking about a wheelie machine with a 72 tooth rear sprocket. That is not even remotely possible. Is the motor just not that powerful or maybe the governor? Just not sure what to look for.
3.5 lacking power
- Thread starter KMR
- Start date
My guesses.
Yes it is possible your governor is causing your concern. By-pass it FOR TESTING PURPOSES ONLY. See if things improve. Don't leave it by-passed.
6:1 with the big diameter rear tire and a 3.5hp won't be fast out of the hole. There just isn't enough torque available especially for an adult.
The wheelie popper comments are more for the stock 8:1 ratio and more hp.
I would say IF your engine is running as it should, then you need a much bigger rear sprocket for the 3.5 hp engine.
Stock was 84 tooth rear I believe. The difference from 6:1 to 8:1 is huge.
Another option, if you aren't concerned with originality, it to put on a $99 Predator 212 and keep the 6:1 ratio.
My thoughts and opinions, others will vary.
Danford1
Yes it is possible your governor is causing your concern. By-pass it FOR TESTING PURPOSES ONLY. See if things improve. Don't leave it by-passed.
6:1 with the big diameter rear tire and a 3.5hp won't be fast out of the hole. There just isn't enough torque available especially for an adult.
The wheelie popper comments are more for the stock 8:1 ratio and more hp.
I would say IF your engine is running as it should, then you need a much bigger rear sprocket for the 3.5 hp engine.
Stock was 84 tooth rear I believe. The difference from 6:1 to 8:1 is huge.
Another option, if you aren't concerned with originality, it to put on a $99 Predator 212 and keep the 6:1 ratio.
My thoughts and opinions, others will vary.
Danford1
I just got this bike about a month ago for my 11 year old. The motor was not running when I bought it and it is not original. I broke the jet screw in the carb it had so I just bought a new ebay carb. I got it running and figured I would let him ride it for a while with this motor and if it wasn’t going to give me much trouble. I know he will get bored of this though and then I will jump to the predator. He has been riding quads since he is 6, so I know this acceleration won’t last. He actually said something today that is why I am posting.
You don't have to go with a Predator, that was just a recommendation for $99 new.
You can put in a 5hp Briggs or 5hp Tecumseh and a lot of other engines.
If your engine runs good, just get an 84 tooth sprocket and new chain. Cheaper and easy. The acceleration will be much better but the top end speed will be lower and a bit safer for your son.
JMO Danford1
You can put in a 5hp Briggs or 5hp Tecumseh and a lot of other engines.
If your engine runs good, just get an 84 tooth sprocket and new chain. Cheaper and easy. The acceleration will be much better but the top end speed will be lower and a bit safer for your son.
JMO Danford1
There is a massive amount of info on Predators. There is a section of this forum for them. You can read, read and read some more.
Also there is a bazillion YouTube videos on modifying them. A lot of vids are made by kids and contain some bad info. Don't believe everything they say. Some respectable guys however produce good videos with good info. Look for Red Beards Garage and Cars and Cameras just to name two.
Link https://www.oldminibikes.com/forum/honda-clone-predator/
Also there is a bazillion YouTube videos on modifying them. A lot of vids are made by kids and contain some bad info. Don't believe everything they say. Some respectable guys however produce good videos with good info. Look for Red Beards Garage and Cars and Cameras just to name two.
Link https://www.oldminibikes.com/forum/honda-clone-predator/
Here is another Good forum for Predator and other engines.
It is a kart racing forum and a lot of guys have to conform to some set of rules. Us minibikers don't have to worry about classes and rules but there still is a Wealth of great knowledge here.
https://karting.4cycle.com/forumdisplay.php?73-Predator
It is a kart racing forum and a lot of guys have to conform to some set of rules. Us minibikers don't have to worry about classes and rules but there still is a Wealth of great knowledge here.
https://karting.4cycle.com/forumdisplay.php?73-Predator
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