Oh God it must be me!!

[phil w]

So now when I start the bike I let it warm up. It all sounds fine, then I rev it slowly and at very low rev i.e just up from tickover I get a ticking noise. This then goes if the revs are increased. Due to my paranoia of older bikes Im wondering if it was a) there before.... and b) F All to worry over ??

[Mezo]

Tappets?

Mezo.

[phil w]

Did wonder tappets but they were set only a few miles ago.

[vander]

I might have the answer.

I have two carburetors for the 660 and both show the same problem.

Watch the carburetor diagram on the parts catalog.

The axis of the "butterfly" (direct translating from spannish, it might not be the correct word...) is a big piece of shit on this bikes. It wears out and so the axis diameter decreases. Then it starts moving and making the noise. With time and use it gets worse and erodes also the hole where this axis sits.

What you get is a very anoying noise and a carburetor that works very bad the higher you ride. Also the bike doesn't ride smooth, the engine stays accelerated, etc.

I have this same problem on my bike.



To correct this, a specialist has to drill the axis hole to fit a purpose made copper case that eliminates the free play. This needs precission.



To check if this is the origin of the noise you can check the free play of the axis from the right side of the bike. You have to remove the tank to see it. With the engine stoped, try to move the axis. Try also with the engine running so you can locate if the noise comes from there.

[phil w]

Cheers Vander... sounds feasable. something else to look at when I get it strippped down again. On the plus side I took it out yesterday and it was superb, so if it is that then it doesnt seem to affect its performance. It tucked away now as its off to Spain on hols... only bummer is I wont be riding for 2 weeks !!

[vander]

Maybe yours is in an earlier stage of wear than mine.

You will feel the un-smoothness when you ride high altitudes. From 1.000m on the problem is evident. You would't believe how bad it feels at +2.600m, like I did this saturday...
Note you would feel this when riding at constant speed. With full gas the problem doesn't exist, as you are already opening the buterfly the maximum possible.

[Chicko]

I went through this same problem with my 660 among other things ie Intake manifolds and O rings,I found that the secondry carb butterfly shaft on my bike was worn quite badly on the left hand side of the secondry carb sitting on the bike also the seals had tottally collapsed. I had it repaired by a mate who built the shaft up and remachined it to original diameter and fitted new seals to it and it now finally runs like a clock

PS I was having all the same problems as Vander

[phil w]

Well back from hols and with nice weather, got the bike out the garage for a spin, ticking does seem to be at the carb area, but it runs just fine, although did have a reluctance to start from cold. Once started though and warm it fires up straight away

[marcm]

What's the Spanish for big piece of shit ?.....I may need it if I have any bike problems on my next travels....us English are so rubbish at other languages...ha ha..