I've decided to post this as a new topic as my problems have changed considerably. I originally started off with a bit of inconsistency with acceleration, nothing bad at all. I took the variator cover thing off and had a look at the belt. It was really loose so i bought a new one, put the bike back together to ride it on what it was before, just a little strange sometimes, but it changed completly. I could barely accelerate. I was pulling out onto 20mph roads with cars piling up behind me, i was going like 12mph. It was rediculous. My new belt turned up yesterday, so i fitted it with high hopes. I got it all back together, sat on the bike, revved it up, and nothing. No movement, i was at the side of the bike full revs and it was going like 1mph. I pushed it down the road and got it going and it sort of kicked itself in, but the bike is now juddering pretty bad at low to mid speeds. Only once reaching like 30mph which takes quite a while does the juddering stop to a level where i would deem it ok. But it still has really slow take off, but inconsistent. Sometimes it sets off faster than others and once im moving the bike responds well to the throttle, but at low speeds the bike BARELY responds to throttle. Any help would be much appriciated as its going to look like im going to have to take this to a garage, which is the last thing i want to be doing at 16, only got some pocket money hahahaha Thanks again, Will.
Take off the belt and measure the width and length, I know its new but its not impossible they could of sent the wrong one. also check the variator nut is tight up against the front pulley, if you have forgot to put a washer back in after you had the variator off it might not be tight to the pulley as it could hit the crank splines first. here a guide of what i mean http://www.pedparts.co.uk/blog/variator-fitting-crankshaft-pulley-spline-damage
Hi, the old belt was about 15mm and really loose. I did some research and this one is supposed to be 18mm. so i searched ebay for gilera runner 50 sp belt and thats what came up. 18mm wide. so i think its right. them pictures are great actually because thats exactly what mine looks like. and yeah i did remember the washer. so its as its supposed to be. nut is as tight as i can get it.
Have you got a center stand or side stand? If you have a center stand that gives clearance to the rear wheel, you could try taking the transmission cover off and open the throttle while watching the variator and clutch operate to see if there is any obvious source of the vibration.
centre stand yeah. I tried that yesterday, but thats when the wheel wasnt really moving at full throttle. now it seems to have settled in, idk, i havent tried it. ive taken everything apart and im going to upload the images in a minute. thanks for the help. also, id say more juddering than vibrations. its like the feeling of driving over those little bumps they put on the floor so you slow down.
Sorry for the spam of pictures. but hopefully you will be able to see something here that flags up maybe. thanks again
I've just got everything back together and ive got much better results. i was riding with pretty much the same, lots of juddering and slow and then suddenly the bike just sprung forward and all the power was back. ive no idea why it did this but its alot better now. just a bit of juddering and sometimes still slow on takeoff. maybe the belt wearing in? also do you think i need new rollers, not necessarily because they are worn, they arent, but because the gearing has changed. the bike actually goes like 5mph+ on the top end. so i was thinking get some different weight rollers to increase my take off?
If you are after a faster take off go for stiffer clutch springs, don't be fooled by the heavy rollers for top speed, lighter rollers for acceleration myth. Hopefully the earlier problems you had was just from the roughness and dirt on the pulleys from the old belt.
As you tune with say an exhaust or 70 kit it changes the revs at which peak power is produced. The aim of having the correct weight rollers in is to hold the revs in the peak power range while accelerating. Here's a guide that explains it much better than i can, http://www.pedparts.co.uk/blog/moped-tuning--rollers There's also a few guides on the forum I think that explains clutch springs in detail too
Ahh. I do still think I might want to change my rollers but I wish I could borrow a set or something. Have a play around see which is best. Guess I'll do some research. That info was really helpful. Thanks for that. With the belt problem, do belts wear in? Like it's worn in a bit and that's why it kicked in again
I have seen people say about belts needing to be worn in but I'm not sure if the wearing in process would cause all the issues you had but time will tell anyway. I've only just got myself another moped so the last time I changed a belt was about 10 years ago and I Don't remember if it had any problems bedding in.
You could also put a 1mm shim washer between the outer pulley face and centre boss to allow it to slip a little more before the belt bites. Also don't forget to replace the plastic fan that should be on the outside of the variator.
Had a bit more time playing around with it and ive got some even wierder results. like 75% of the time its fine, fast take off and top speed. although every now and again when i stop at traffic lights for example. i will go to set off... and nothing. full throttle and im not moving. I had to push my bike today, get it going down a hill and it kicked back in. But, when it does this slow thing, ive worked out how to fix it. It was going really slow the other day and i aggressively swerved around something in the road and it kicked back in. So now, ive worked out by physically shaking the bike when its going slow, it makes it kick back in. I know this sounds weird but it works every time. ill be going super slow like less than 10mph at full throttle and then i shake the handlebars side to side, the engine rpm goes low, then it kicks in full speed again. I know this sounds like a joke but its as if it whip it to keep it going hahahaha I really cannot understand why that would fix it, and what even is the problem in the first place. I bought some heavier rollers and the problem increased, so ive swapped the old rollers back in, about 5.5g and its ok, sometimes goes slow but ok most of the time, i can deal with it for now basically. But, i was checking for flat spots again, there arent any flat spots but they are actually worn down a tonne. on one side of the roller most of the black plastic part is worn down to the metal and on the other side its fine. so i think maybe thats what is causing the juddering????? because ive taken them out and put them back in, so now they are not worn together like they were before. So im going to order some new 5.5g rollers and hope that the juddering is fixed, but do you think this could fix the random times when my bike just wont move xD