Above 30 mph bogging in colder temp By seanstr (Read 9,023 times)

[seanstr]

OK for now, OEM contra spring, 9 gram rollers. 799 x 19 x 28 belt, what is supposed to be on a Lance 125cc engine.

Koso variator still not in. Still waiting for 2 k contra spring.

Will drive to work, hoping for better top end.


Do one change and check results.

[seanstr]

So the ride in to work was weird.

I had bogging again. I adjusted the air fuel mixture screw. It helped but it still bogged down once more, I'll report again on way home.

My initial thoughts are that 9 gram rollers are incorrect. However I'm still not getting good take off. It's still acting like it's in second gear from idle. If the belt is too short or too loose it would do this correct?

I had the cover off watching the belt. It's sloppier than I like. It's a new belt. 799 x 19 x 28.

I still think the longer belt, with stronger contra string (2k) then play with the weights?!?

Do one change and check results.

[seanstr]

I am sure that the scooter is starting in second because the belt is too short.

Put on 835 belt and left the 9 gram rollers. Still don't like the take off.

I think the 835 is too long but the 799 is too short.

I'm at a loss.

Any ideas would be great.

Do one change and check results.

[jct842]

I don"t know what the differences are between yours and a long (10 bolt) 150 case are but I used an 842.

A short belt is going to limit the range of both pulley sets, the variator and the clutch.

On take off the rear clutch pulley needs the belt at the top. At max speed the variator has the belt at the top.
The performance variator is slightly larger in diameter and if the motor has enough balls the belt will climb still higher with the larger dia pulley.

[seanstr]

Nov 25, 2016 21:30:42 GMT -6 jct842 said:

I don"t know what the differences are between yours and a long (10 bolt) 150 case are but I used an 842.

I counted 9 bolts. Talked to mechanic (guy I trust) he stated service manual for the engine states 799 x 19 x 28 but we both thought what if they had different engines that year. He's going to check on diameter of the OEM boss for variator.


A short belt is going to limit the range of both pulley sets, the variator and the clutch.

This is exactly what I see. The 799 is not going all the way.

On take off the rear clutch pulley needs the belt at the top. At max speed the variator has the belt at the top.
The performance variator is slightly larger in diameter and if the motor has enough balls the belt will climb still higher with the larger dia pulley.

With the longer 835 belt it goes to edge of the stock variator, however still only getting to 45 mph. RPM's are always at 7000. It feels like the 835 is slightly loose. My next question. If the 1.5k contra spring make belt tighter, will the 2k spring make it even tighter and hopefully tight enough to take up the slack? Also if the slack is taken up and it stops being sloppy, will I then be able to properly tube this CVT with weights?

Comment: when I get the malossi variator installed (whenever it gets here) I understand it will be better for take off and smoother over all performance. This combined with the strongest contra spring, longer belt, if I still don't get too mph 55+ I'm going to go for mpg.

Right now I'm getting only 61-62 mpg. It should be 80-90 mpg.

If i give up on the mph, what is the best combination for fuel economy?

[jct842]

This is just me but if my scooter will not go past 45 while only making 7000 I would blame the engine. It seems to me that it does not have the balls to go any faster. Until the engine has more hp I really do not see that it is going to go any faster. No engine is going to give good mileage when run at WOT.

[seanstr]

Nov 26, 2016 8:40:25 GMT -6 jct842 said:

This is just me but if my scooter will not go past 45 while only making 7000 I would blame the engine. It seems to me that it does not have the balls to go any faster. Until the engine has more hp I really do not see that it is going to go any faster. No engine is going to give good mileage when run at WOT.

I can get it to go a bit higher in RPM's but only like 500 more maybe.

I checked the service manual and the thing says valve clearance is .002 for both not .004.

It does tap like it's loose a bit but I can't verify its for mine.

I'm going to go pull my paperwork and see.

Maybe mine will tell me.

Oh, and my compression test is getting with WOT is 185 psi.

[seanstr]

Nov 26, 2016 8:40:25 GMT -6 jct842 said:

This is just me but if my scooter will not go past 45 while only making 7000 I would blame the engine. It seems to me that it does not have the balls to go any faster. Until the engine has more hp I really do not see that it is going to go any faster. No engine is going to give good mileage when run at WOT.

Also why is it only 7000 RPMC's? I thought that would be good for 125cc.

I need to get to 8000 RPM'S. I see that now.

[jct842]

If your compression is 185 you need to be using premium gas too. My question now is why is the compression that high. Around 150 is more like what a gy6 is. Could your engine be Carboned up? 2stroke engines do that commonly though not impossible for a 4 stroke to do it.

[seanstr]

Nov 26, 2016 12:25:03 GMT -6 jct842 said:

If your compression is 185 you need to be using premium gas too. My question now is why is the compression that high. Around 150 is more like what a gy6 is. Could your engine be Carboned up? 2stroke engines do that commonly though not impossible for a 4 stroke to do it.

No that's what is to speck. At least per Sym. 184.7 something.

[seanstr]

OK, so I have the 2k spring in. The belt isn't loose. Yeah!

Tried 13 gram sliders. 45 mph top end still. Lol.

Trying 10 gram rollers, then either up or down depending on how it feels. Hoping for like some more top end.

Do one change and check results.

[jct842]

If 185 is spec then it is a high compression engine. Hi test!

Max torque is usually given at around 7500 rpm for a gy6

The only way you will get more speed is more rpm.

Lighter weights and longer belt comes to my mind. You are probably messing with the wrong scooter because even if you got a 10% increase you are still looking at getting a lot more out of it. 10% is a lot to get out of one of those engines with out major work on it.

[seanstr]

Nov 26, 2016 18:13:54 GMT -6 jct842 said:

If 185 is spec then it is a high compression engine. Hi test!

Max torque is usually given at around 7500 rpm for a gy6

The only way you will get more speed is more rpm.

Lighter weights and longer belt comes to my mind. You are probably messing with the wrong scooter because even if you got a 10% increase you are still looking at getting a lot more out of it. 10% is a lot to get out of one of those engines with out major work on it.

My problem is in just trying to get it back to OEM. It used to do 55mph, and got 80-90 mpg. Then it got in to Oct if 2012 and the temp dropped to under 60 degrees Fahrenheit. Got bogging, drop in mpg by like 20 mpg, and a drop in mph, by 5-10 mph.

Shop said they couldn't figure it out. Ever.

They did stuff to it and wouldn't tell me what. Still don't know. It was under warranty. Lance stated that the shop said they fixed it but it would never go any faster.

So, here I am.

[seanstr]

Well, I tried several things after getting a copy of a fiddle 2 125cc service manual.

Tried valve clearance of .002. compression went down to 165 psi. So back to .004.

I'm currently waiting for a Malossi variator. Once that's in I'll try to adjust there CVT yet again.

Any idea are extremely welcome.

Do one change and check results.

[seanstr]

Please, also need make suggestions for fuel economy.

I am going to have give up the mph I think. Just seems impossible. Nothing changes the outcome of only getting to 45mph.

I want the higher mpg. I only need to go 40 mph.



Do one change and check results.