Timing Belt Slipping Off

[cuong nguyen]

Hey guys have almost finished my build but keep running into the problem with the timing belt. It keep slowly slipping off.

I've tried to get the tensioners as straight as I can but it still slowly slips off.

Any help would be much appreciated.

[Ben C34]

Hav you got the guide plates either side of the bottom pulley?

[jiffo]

Unless the idler is mounted on a machined surface you're in trouble.

Belt will track true if everything is machined square to the line of cams/crank.

[nicksamaniac]

If the idler and tensioner are both mounted against a flat machined (square) surface then it will track correctly,

It will only walk off if somthing is guiding it off -ie some parts is not square to the rest of the setup.