Z900-A4 Cam Chain Top Idler.

[Paul Whitehouse]

Hi,

Been hearing a noise from under the cam cover of my Z900-A4 getting progressively worse. It appears to be coming from the central tunnel...on startup it idles ok, but when 2000 rpm is reached the noise starts...almost a vibration...taking it beyond 2000 rpm and the noise dissappeares but not running right.

Took the rear tensioner apart yesterday and all fine. Took the cam cover off and inspected the top idler assembly. The gear had a lot of movement (in all planes)...is this gear normally free floating (never had a good look at one of these closely before) or is this a sign that the idler assembly is worn...certainly seems as this could be the cause of the noise and the 2000 rpm mark could be it's sweet spot when all the resonance / noise starts.

Cheers.

[Pigford]

Probably worn - how do the 4 x rubbers look - most likely gone hard.

[Paul Whitehouse]

Hi Mr P.....rubbers rock hard and brittle...possibly the originals. Just had a search on the net and it looks as though, if this is worn, I'll have to buy the complete assembly...ouch!!

[zed1015]

There should be only minimal side float of the gear in it's mount of about 1mm, anything else radial or otherwise is excessive wear.
Some models of top idler bracket allow the gear to be replaced without having to buy the complete assembly.

[Paul Whitehouse]

Cheers Rob....it's one very worn top idler assembly in that case !. Looks as though the gear is captive in the assembly on mine. Anybody know the best (cheapest) place to get a replacement ?

[zed1015]

The best and cheapest is a Liska racing item at $84 (£50) as opposed to OEM from Zpower at £180.
The liska item is also re-buildable.
Even with shipping from the states you will save a massive amount and get a superior item.
You will have to email Liska with your order as their site is not set up for UK shipping but otherwise there should be no problem.
They also stock the four mounting rubbers and anything else that may be needed.
http://www.liskas.com/servlet/the-Cam-C ... Categories

[z1bman]

http://www.liskas.com/servlet/the-12/ca ... %2C/Detail

[Paul Whitehouse]

Thanks for the information guys....Liska Racing here we come !!

[ZedHead]

I think I need to get some Liska stuff in

[zpower]

I think I need to get some Liska stuff in

And APE stuff like main bearing studs and cylinder studs for a start

[ZedHead]

I think I need to get some Liska stuff in

And APE stuff like main bearing studs and cylinder studs for a start

I am on it Phil