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Transmission/belt noise
Posted: Wed Jul 27, 2016 3:29 pm
by FunkeyMonkey
Just installed new polini belt and 9:1 gears and noticed this noise when I rev. Is this something to be concerned about or noise to be expected with changes made?
https://youtu.be/QkiwXBOvKug
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 3:59 pm
by ped
Hi FM you can use a piece of hose from ear to the motor. To pinpoint where the noise is coming from.
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 4:52 pm
by Rip_City_Spree
If it didn't do that before I'd take it all apart to make everything got put back together properly.
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 5:37 pm
by FunkeyMonkey
Ok, ill take it apart and look at it. Not sure what could be causing it, i only took drive pulley off and right.back on for new belt. Took clutch off and right back on after I put in new gears.
The polini belt I bought does says it's a performance belt and wider than stock, would that cause the sound?
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 6:46 pm
by Meatball
I know this is could prove to be completely irrelevant to your problem but after installing Taz gears in my Spree, it makes a different sound. Like a gear noise. Im up to about 500mi after the swap without a single problem.
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 6:50 pm
by MrJumps
I belive the gears he offers is straight cut gears or whinning gears.
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 7:12 pm
by FunkeyMonkey
Whinning gears?
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 7:27 pm
by bonesv
FunkeyMonkey wrote:Just installed new polini belt and 9:1 gears and noticed this noise when I rev. Is this something to be concerned about or noise to be expected with changes made?
https://youtu.be/QkiwXBOvKug
You should remove the kicker cover and inspect before running it again. You may have tightened the front pulley (variator) against the belt and it is not actually tight to the crankshaft. Install the variator and outer drive face first, then slip the belt in and re-install the clutch assembly last with the belt pulled down into the sheaves of the rear pulley. Did you install a new variator boss? If so, is it longer than the stock one? That could be causing the noise if it is rubbing the kick starter mushroom gear. Let us know if you have done this check already. I would not run the motor until the problem is discovered. Bones
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 9:04 pm
by FunkeyMonkey
bonesv wrote:FunkeyMonkey wrote:Just installed new polini belt and 9:1 gears and noticed this noise when I rev. Is this something to be concerned about or noise to be expected with changes made?
https://youtu.be/QkiwXBOvKug
You should remove the kicker cover and inspect before running it again. You may have tightened the front pulley (variator) against the belt and it is not actually tight to the crankshaft. Install the variator and outer drive face first, then slip the belt in and re-install the clutch assembly last with the belt pulled down into the sheaves of the rear pulley. Did you install a new variator boss? If so, is it longer than the stock one? That could be causing the noise if it is rubbing the kick starter mushroom gear. Let us know if you have done this check already. I would not run the motor until the problem is discovered. Bones
I'm pretty sure i tightened the drive face first then slipped belt on but ill double check, no new variator..in fact i never even touched it, it stayed exactly where it was, just took drive face off so i could remove old belt and put new one on. all i did was install new gears and while i had it opened i installed a new polini belt.
PS the noise it makes seemed to only happen when a little throttle is given, didnt hear it at idle at all.
Waiting til it gets a little cooler outside then ill check out it.
Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 9:12 pm
by Meatball
Yeah, they whine pretty good. Sounds like a turbo spooling up. I actually like the sound. Makes me think its fast!

Re: Transmission/belt noise
Posted: Wed Jul 27, 2016 9:48 pm
by bonesv
I had another listen to that and it makes sense that if it's not making any noise when it's at idle, then it's probably the gears. The real noise I heard was from the air filter. Try revving it on thr ground with the rear brake applied so the gears will not spin the wheel. If it does not make that noise then you may have located the source. Noise from the belt or variator/rollers, etc. would show up anytime the motor was running. Bones
Re: Transmission/belt noise
Posted: Thu Jul 28, 2016 4:25 am
by Peteyparado
Try lifting the scoot so rear tire off the ground an try spinning it an c if u get a Slite noise or removing the belt an starting it an listen..
Re: Transmission/belt noise
Posted: Thu Jul 28, 2016 4:43 am
by ped
Put your old belt back on.

Re: Transmission/belt noise
Posted: Thu Jul 28, 2016 9:39 pm
by FunkeyMonkey
Ok bones you were spot on, pulled the cover and in fact i did tighten it onto the belt, the drive pulley wasnt completely in. Removed the belt re-tightened everything correctly..If I electric start with the cover off..holding the starting gear in place so it doesnt move and hit the drive face everything seems fine; that noise is gone and everything sounds pretty normal until i get little high in rev and then i hear a little rattle noise, almost sounds like the starter gear.
While i had the side cover off the kick start gear fell out that mates to the driven pulley. Now I cant seem to get it back into proper position. If i try and kick start i hear a little grind noise and it wont kick over, it feels like the gear is snagging on the inside, im sure i have it installed wrong.
PS so i looked up on the wiki and saw a picture of a spree kickstart and realized i did have it put back wrong. Ill fix it tomorrow after work and see how it does.
Thanks
Re: Transmission/belt noise
Posted: Thu Jul 28, 2016 9:55 pm
by bonesv
Wow! Good news! Yea, that bendix gear has to go in just right to pop into the bushing it rides in. Be careful - you don't want to bend your crankshaft by prying on the drive face. If you bent it, it could cause vibration or worse. Glad you have got the belt on successfully!
