What would cause these symptoms? By danny (Read 1,602 times)

[danny]

what would cause the engine being reved but not engaging the back wheel unless I use abnormally high amount of throttle? 

For example, it will idle properly and rev but usually when I rev it alittle, the back wheel will take off but now its not doing that anymore. Now I have to rev it abnormally high just to take off. I checked the back wheel and it moves freely and the brake is not too tight or engaged. I have been adjusting my valves because I haven't got them right but I don't think thats whats causing this because I have adjusted them several times and still the same. It seems there is some friction going on near the belt or clutch area but I thought it was ok after an issue occured recently but ever since, it has not been the same. I just installed a new belt and also just dealt with something wrong in that area. There was a metal piece that broke off of the casing and got stuck in the clutch and I had to remove the clutch to free that broken piece. Is it possible that I have to completely disassemble the clutch in case other parts got jammed and maybe thats why there feels like some friction. Or does it sound like it could be something else?

Thanks

[danny]

I thought I would ask to see if it might be something else that is common rather than disassembling and it not being it and possibly something else

[jct842]

Your going to have to open it up. What engine is it? Numbers on engine case by the kickstand mount lower left side. Could be belt worn, variator, or clutch. If it is a 150cc you can pull the cover and run the engine to see what is causing it.

Just noticed you have put a belt on. Put marks on inside of the variator from the center to the very top and run engine to top speed watching to see where the marks get erased. The belt needs to go to the top of the variator pulley.

[danny]

I took it all apart again and I did not completely disassemble the clutch after I spun it and realized it spins very freely and likelt is not causing what seems like friction. It seems to be the variator that doesn't spin very freely but that might be normal so im wondering if there is a way to gauge if the variator is spinning with the proper tension when spun by hand. 
 
Thanks

[danny]

Top speed 23mph What could be the problem? As my scooter stopped working, I finally figured out the cvt case had a small stop piece for the kick stand inside break and fly around and I think got caught in the clutch area and thats why the belt wasn't moving at all. I finally figured out that I needed an impact to get that nut off of the clutch and so finally out dropped the broken piece. Now, it would not go fast again struggling at about 20-22mph and I still have not figured out why. I don't think another piece is still stuck somewhere because the piece that fell out looked complete and when I spin the clutch with my hand, it spins freely. The variator on the other hand does not and im wondering how to test it.

The picture below is the racing variator with over 8mm of marking for the suggested experiment and if you look near the middle, there looks to be small scoring lines like as if something got jammed in it or from belt wear. I installed a new belt and rollers after that and tried again. I plan to smooth out that pulley with sandpaper next.  I tried the stock variator and i put marks on it as well to see if the belt was reaching the top and it did, unlike this racing variator where there is about 8mm worth of markings still there but with both, I still only got up to about the same speed (20-22mph) , though the marking completely disappeared from the stock. Im not sure how to troubleshoot something like this so your help would be very much appreciated. 

[danny]

bump

[danny]

bump

[danny]

I sanded down the score marks and tried again and the mark is still about 8mm.

[danny]

what does it say if that happpens that the belt is not reaching the top or what would be the next troubleshooting steps be if that happens?

[danny]

any tips / suggestions?

[jct842]

normally if it does not go to the top you add weight, but I think you may have other issues. Like go to the next size heavyer weights. Wish alley was here this is right up his alley!

What happens if you put the scooter on the center stand and rev it all the way up? what does the tach say wide open? on stand and on the road? Just wonder if the variator got damaged from the piece of metal jambing the clutch. Think that is where the grooves probably came from on the v face. you did check that the rollers are in the right grooves behind the face of it?

[danny]

already checked the rollers, even tried putting new ones and the stock variator and I do not have a tach. Maybe Ill have to try heavier weights.

[jct842]

Does it Rev up quickly like it should? It is really pretty hard to go thru this with out a tach.

There are some cheap ones that run about a dozen bucks, they are pretty slow to follow the engine speed but they still are very useful.

[danny]

yes

[danny]

I think its possible it could be the new kevlar belt that I bought off ebay but im not sure. I just started it to see I could hear anything and I thought I heard the belt slipping but I could be wrong. Is there any way to run the engine without the case because my scooter usually needs the case with the kick start mechanism in it? I wouldn't know if its actually the belt unless I bought a new one because the old one oddly seems to big now
Thanks