Gilera Dna Loose belt

[Bpor]

Hi,
I have a Gilera Dna 180 and about a year ago i changed the driving belt. The problem is that the belt is loose!! it can be moved several mm in the middle. Also now the top speed of the bike is now 100k/h instead of 120k/h

Now i opened again and found out that the a part of the belt came off (one of those teeth), and there is a lot of rubber on the inner part of the pulley on the engine side.

does any one know why this. i measure the width of the Belt (~20.8mm) and when compared with the Haynes manual that's ok!!

Anybody knows what happening???

thanks

bpor

[jmkjr72]

well a few questions
is the scoot stock or have you moded it in any way if you have chaned the varatior you need to make sure the belt runs true still if you still have the stock varatior if you ever took it out you need to make sure all washers/shims go back in in the proper order

secondly did you get a stock oem belt an after market oem belt or a performance aftermarket belt

the reason i ask is on some other brands we have found that the after market oem type belts may not be the right size

[Bpor]

I bought the bike second hand so i dont know what happened before. I replaced some parts of the variator but the parts bought are not performance. And i used a haynes manual to make sure al the components are in order. the belt i used is an aftermarket one bought here:
http://www.gileraspares.co.uk/spares/pa ... PN=VB90991

Do you think that this one is better since OEM:
http://www.gileraspares.co.uk/spares/pa ... =Z=95%3E5=

I tried to look closely and it seems that the belt is the correct width but too long since is when i tensioned int with my hand it moved down close to the center of the pulley an not toughing.

Thanks a lot for the reply

bpor

[jmkjr72]

i know its a big diffrenc in price but i would stick with the oem when an after market is 1/2 the price of a oem you have to wonder why it is that much cheaper

when you have the belt cover off can you run a staight edge from the top of the trans to the bottem without the belt hitting it
if you can when you get the new belt on start the engine with the cover off rev it quick so the new belt is seated
now shut it down
take the straight edge and measure from the straight edge to the belt in several spots near the varaitor and near the clutch these dimenson should be very clost to each other the best tool to use for this is a dial or didgtal caliper and you want to use the rat tail end of it
if the measurment by the varatior is smaller then by the clutch you need to remove shims from behind the varatior
if it is larger you need to add shims behind the varatior
ie if the front is 0.980 and the back is 0.990 there is a 0.010 diffrence (i wouldnt worry about such a smal one but this is just theory) you need to add a 0.010 shim to the front to move the belt into alingment

and if the mearusments were front 0.990 and rear 0.980 you will need to take the shims out of the front measur them and find one that is 0.010 smaller