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  #21  
Old 02-19-2020, 11:17 AM
Shax90 Shax90 is offline
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Quote:
Originally Posted by Ebrownie View Post
26” tires are pretty large, with an 7:1 ratio at 3600 rpm you’d be doing around 40 mph. That’s some pretty tall gearing. My guess is that your engine doesn’t have enough power or air flow to run any higher RPMs. I’m not sure what your muffler system looks like, but that could limit rpm. My kart engine is exactly the same as yours except for just a header for the exhaust. I lost almost 1000 RPMs on the top end when I switched the stock exhaust back onto the engine from the straight pipe. The airflow makes a big difference.

I’m not sure what kind of top speed you are looking for or currently getting, but I would say gearing down wouldn’t hurt. You’ll have better acceleration and most likely higher top end rpm.

I had the stock one on it originally but once I put my home made one on it added some speed it's only getting up to 32 but my torque converter wont engage so that's why I'm trying to get a bit more rpms

---------- Post added at 01:17 PM ---------- Previous post was at 01:06 PM ----------

Quote:
Originally Posted by Whitetrashrocker View Post
I get the "want to go faster".

40 in a small kart is pretty fast. I don't know where you ride but Ive got wide open flat dirt. I'd love to be able to break 40mph and I can gear for it, but I find it so much funner to gear lower and have a tire fryer that tops at 30-35mph.
When the rear wants to get in front and you can drift and donuts all day long it really puts a smile on my face.
I'm doing more street riding it's a dirt bike frame that I'm turning into a "motorcycle" of sorts so I'd like to at least get to 40 if possible
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  #22  
Old 02-19-2020, 12:29 PM
karl karl is offline
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Quote:
Originally Posted by Ebrownie View Post
26” tires are pretty large, with an 7:1 ratio at 3600 rpm you’d be doing around 40 mph.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

You need more power, or change the gear ratio "steeper", like 9 or 10 to 1 , so the motor can rev higher, and get the torque converter shifted into overdrive

To put it in perspective, if your motor had enough power to turn 5500 rpm and float the valves, you would be travling over 61mph, and it seems like your almost at half that,

so lowering your gear ratio might make the kart go faster, accelerate better, and wear belts less.
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  #23  
Old 02-19-2020, 02:09 PM
Shax90 Shax90 is offline
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Quote:
Originally Posted by karl View Post
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

You need more power, or change the gear ratio "steeper", like 9 or 10 to 1 , so the motor can rev higher, and get the torque converter shifted into overdrive

To put it in perspective, if your motor had enough power to turn 5500 rpm and float the valves, you would be travling over 61mph, and it seems like your almost at half that,

so lowering your gear ratio might make the kart go faster, accelerate better, and wear belts less.
Thanks! That was one if my thoughts I was just avoiding it so I didnt have ti buy a new chain and sprocket😂
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  #24  
Old 02-19-2020, 02:12 PM
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Whitetrashrocker Whitetrashrocker is offline
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You say your TC won't engage. What do you mean by that?
If your getting that fast with it stuck in low....
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  #25  
Old 02-19-2020, 02:20 PM
Shax90 Shax90 is offline
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Quote:
Originally Posted by Whitetrashrocker View Post
You say your TC won't engage. What do you mean by that?
If your getting that fast with it stuck in low....
Ya it's still in low the pulley around the drive shaft fully opens but the one on the right with spring isn't opening up. Does it normally plato for a while before it engages because at the moment the length of road I've driven it on is about 1/8 mile maybe a tad longer.
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  #26  
Old 02-19-2020, 02:32 PM
karl karl is offline
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Quote:
Originally Posted by Shax90 View Post
Ya it's still in low the pulley around the drive shaft fully opens but the one on the right with spring isn't opening up. Does it normally plato for a while before it engages because at the moment the length of road I've driven it on is about 1/8 mile maybe a tad longer.
If the load on the torque converter is too great, and the motor cannot maintain/gain rpms, it will stay in a lower gear to compensate.

Did you try running it on jackstands, and observe clutch function with no load?

Even if the torque converter is working exactly as it should, with your gearing, it simply will not preform as well as it could.
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  #27  
Old 02-19-2020, 02:38 PM
Shax90 Shax90 is offline
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Quote:
Originally Posted by karl View Post
If the load on the torque converter is too great, and the motor cannot maintain/gain rpms, it will stay in a lower gear to compensate.

Did you try running it on jackstands, and observe clutch function with no load?

Even if the torque converter is working exactly as it should, with your gearing, it simply will not preform as well as it could.
Yes it opened up much greater when I lifted it. I think o just have to adjust the ratio I was just trying to avoid it
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