CSC TT250 overheating?

SirStogy · Today, 03:49 PM

Hello all,

I'm new here. I've used the site to find some good info in the past but now have a question I cant seem to find an answer to. I have a pretty new TT250 that rides nice and smooth but after about 5 miles, regardless of the weather, the clutch gets chunky and it lags when I take off from a dead start. Sort of jumpy. It's very noticeable and the only thing I can think of is that it is over heating quickly. But whether it's the hot sun or 3am rain, it will always do it towards the end of my ride. I use the proper gasoline, have changed and tested thicker oils, I cant figure it out and the mechanic didnt seem to want to investigate too much (he was a bigger fella and didnt want to ride too far). Any help y'all can give would be really appreciated.

J4Fun · Today, 04:33 PM

My thoughts, valve adjustments first, and are you using the proper oil for the clutch?

SirStogy · Today, 05:04 PM

I have adjusted the valves several time and all seems well with them. I have also used the recommended oil but have since switched to 10w40 I believe it is. I could be recalling incorrectly tho.

Thumper · Today, 07:14 PM

What you are describing could be lean jetting. "jumpy" and lags off the start, and running hot are all reasonable explained by lean jetting.

Have you drilled out the airscrew? What jets are in there. It is pretty common for OEM jetting to be lean for emissions reasons.

SirStogy · Today, 07:33 PM

I bought a jet with a bigger hole and installed it but that caused it to jerk pretty violently and shut off at times. I changed it back to stock, though I'm not sure what size the stock one is.
I would take it to another shop for unfortunately the mechanics don't want to touch it.

Thumper · Today, 09:02 PM

There are numbers on jets. Get a pair of reading glasses or a magnefying glass. You need to know the actual numbers.

SirStogy · Today, 10:50 PM

So it looks like the stock is #108 and I tried the #112 and it didnt run right. Would raising that ring on the needle in the carb maybe help?

Today, 07:14 PM	#4
Thumper Join Date: Feb 2021 Location: Kansas City Posts: 2,741	What you are describing could be lean jetting. "jumpy" and lags off the start, and running hot are all reasonable explained by lean jetting. Have you drilled out the airscrew? What jets are in there. It is pretty common for OEM jetting to be lean for emissions reasons. __________________ No matter where you go, there you are
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Today, 09:02 PM	#6
Thumper Join Date: Feb 2021 Location: Kansas City Posts: 2,741	There are numbers on jets. Get a pair of reading glasses or a magnefying glass. You need to know the actual numbers. __________________ No matter where you go, there you are
	0

Today, 03:49 PM	#1
SirStogy Join Date: Nov 2024 Posts: 4	CSC TT250 overheating? Hello all, I'm new here. I've used the site to find some good info in the past but now have a question I cant seem to find an answer to. I have a pretty new TT250 that rides nice and smooth but after about 5 miles, regardless of the weather, the clutch gets chunky and it lags when I take off from a dead start. Sort of jumpy. It's very noticeable and the only thing I can think of is that it is over heating quickly. But whether it's the hot sun or 3am rain, it will always do it towards the end of my ride. I use the proper gasoline, have changed and tested thicker oils, I cant figure it out and the mechanic didnt seem to want to investigate too much (he was a bigger fella and didnt want to ride too far). Any help y'all can give would be really appreciated.
	0

Today, 04:33 PM	#2
J4Fun Join Date: May 2021 Posts: 359	My thoughts, valve adjustments first, and are you using the proper oil for the clutch?
	0

Today, 05:04 PM	#3
SirStogy Join Date: Nov 2024 Posts: 4	I have adjusted the valves several time and all seems well with them. I have also used the recommended oil but have since switched to 10w40 I believe it is. I could be recalling incorrectly tho.
	0

Today, 07:33 PM	#5
SirStogy Join Date: Nov 2024 Posts: 4	I bought a jet with a bigger hole and installed it but that caused it to jerk pretty violently and shut off at times. I changed it back to stock, though I'm not sure what size the stock one is. I would take it to another shop for unfortunately the mechanics don't want to touch it.
	0

Today, 10:50 PM	#7
SirStogy Join Date: Nov 2024 Posts: 4	So it looks like the stock is #108 and I tried the #112 and it didnt run right. Would raising that ring on the needle in the carb maybe help?
	0