Acceleration decreased after cleaning and lubing clutch

[moisesanguiano]

Hey all, so I ordered 1,000 rpm contra and clutch Springs to put on my 150cc sunl. When I took off the clutch and pulley, I noticed that it was pretty dirty in there, especially on the "tube" where one pulley half slides towards and away from the other half. It looked like dirty grease mixed with a little rust (pretty much orange grease). So I completely stripped down the pulley and clutch and cleaned out everything, and I mean EVERYTHING. I re-greased all the sliding parts, switch out the springs, and put everything back together. When I took her out for a ride, I immediately noticed lack of acceleration, and it took a while to get up to speed. When I accelerated on the center stand, the rear tire started spinning around 2,000 rpms. Before, it used to spin around 3,000 rpms. Now correct me if I'm wrong, but i read up that these performance clutch springs are supposed to engage that many more rpms on top of stock. So since the stock Springs engage at 3,000, I assumed with these springs it would bump it up to 4,000 rpm engagement. Instead they engage 1,000 rpms lower. Wtf??? So I tore it all apart and put in the stock contra and clutch springs. Now acceleration is a tad better, but it still takes awhile to take off. It's nowhere near where it used to be. I'm wondering if somehow, since I cleaned everything out, it's affecting acceleration? Maybe the pulley/clutch is working too smoothly? Before, it was a pain to open the pulley by hand, but it was possible. Now it's tons easier to do it, with the stock and 1,000 rpm contra spring. Fwiw, before I installed the performance springs, I noticed the contra and clutch springs seemed to be weaker than stock. Both contra springs have the same number of coils, but I think the perf spring is easier to compress. As for the clutch springs, they have one coil more than stock (stock has 5, blue 1,000 rpms has 6). I looked into the 2,000 rpm springs, and it seems the clutch springs have the same number of coils as my stock springs. Anyone have any input?

[DisillusionedPrepper]

You are correct on all counts. You made the halves open easier by cleaning them. Plus some of the new grease will get into the clutch bell/pads. I use Dupont Teflon spray for the clutch parts. It sets up dry, and won't melt with the heat back there.

Also, when you buy springs buy ONLY Malossi or Polini. These brands I know are stiffer than the OEM. All the other brands I have tried are weaker or the same.

Your best bet is to place a bathroom scale on a drill press. Then use the chuck to compress the spring to a given height. Record the "torque" reading.

Usually the more winds on a clutch pad spring means a weaker spring. More winds = thinner gauge wire...

I recommend the Polini spring sets, and give your other new springs away.
The other quick cure is to go lighter on the rollers. Maybe 1/2 the weight of what you have now. The pulley spring, and the rollers work as a pair so lighter rollers will have the same effect as a heavier spring

[moisesanguiano]

Hello again DisillusionedPrepper! I opened the clutch back up again today. The pads and bell looked clean and dry, but i went ahead and cleaned them again. As far as the rollers, I've already ordered a couple of sets and they should be coming in later today. I'll try them out and see what happens. Also, I'll look into those spring brands and see if I can pick up a set. Thanks for your help

[DisillusionedPrepper]

No trouble.

I have a "thing" about opening engines over, and over again... I DON'T LIKE TO!!!
The more times you open these cheap engines the more of a chance of stripping a thread somewhere.

Try your new rollers first. You may have to go lighter than you think because your control spring is now weaker.
Something else that I like, and use is the Malossi torsion controller. Its a simple nylon type "pad" that sits under the clutch itself, and on top of the spring. It sort of pre-loads the spring, and eliminates the metal to metal contact between the spring, and clutch.

If they do not have them for the 150cc engines, I plan to make one. It's just a nylon shim about 1/4" thick with a groove that the spring seats in. Simple enough...

Post up your results. We all like to read a success story, and the trial, and error that goes along with it.

Best to ya!

[blueboy5000]

Generally, for a daily-drive 150 gy6, I use stock contra spring and RED shoe springs mated to a steep-ram 115mm variator w 12g flat slides. Variator mods make a much bigger acceleration gains rhan clutch mods. Clutch mods are pretty pointless unless you're building a drag-scooter