noisy top end after rebuild.

#1 PostAuthor: **chrisu** » Wed Jun 08, 2016 2:58 pm

Bit stumped on this one.

Engine was quiet when bike was brought to me but smokey so has had a top end rebuild.

rebore/new pistons - all seems fine.

Head was rebuilt - new valves, guides and seals. Came back to me with valves etc all assembled. Also has all new camchain idler gears etc.

Fitted pistons, barrels, head, cams etc and timed up.

When I ran it there was a ticking noise from the top end - it increased with revs and is mechanical in nature. engine seems to run fine - no smoke etc.

Have dismantled the head and can't see anything obvious (like a sticking valve or loose valve guide) so before i reassemble and see if its 'gone away' - very unlikely any thoughts on possible cause ?

I've rebuilt loads of heads before and never had this symptom before.

I have fitted the cams in the head without the valves and there is no up/down play but there is quite a bit of end float.

Thoughts ?

warren3200gt · #2 PostAuthor: **warren3200gt** » Wed Jun 08, 2016 3:50 pm

Could you have accidentally put the valve buckets back on different valves? I have no 4 exhaust bucket that "ticks " a bit.

Pigford · #3 PostAuthor: **Pigford** » Wed Jun 08, 2016 4:10 pm

Could just be a bit of extra end-float :?:

weaver · #4 PostAuthor: **weaver** » Wed Jun 08, 2016 4:14 pm

leaking exhaust gasket?

Kev1R · #5 PostAuthor: **Kev1R** » Wed Jun 08, 2016 4:49 pm

Carbs out of balance can cause what sounds like mechanical noise.

#6 PostAuthor: **chrisu** » Wed Jun 08, 2016 5:39 pm

weaver wrote:leaking exhaust gasket?

thanks but no

#7 PostAuthor: **chrisu** » Wed Jun 08, 2016 5:40 pm

Kev1R wrote:Carbs out of balance can cause what sounds like mechanical noise.

nope - balanced them.

its a mechanical ticking noise from the top end

#8 PostAuthor: **chrisu** » Wed Jun 08, 2016 5:40 pm

should have said - its not a light tick more of a louder tap.

PAULJAC47 · #9 PostAuthor: **PAULJAC47** » Wed Jun 08, 2016 5:44 pm

Not a z thou a2 by any chance?

z1bman · #10 PostAuthor: **z1bman** » Wed Jun 08, 2016 5:47 pm

sounds like end float noise have you inspected the two cam caps which control the end float for misalignment damage ?

SVENLEATHER · #11 PostAuthor: **SVENLEATHER** » Wed Jun 08, 2016 9:00 pm

Hi chris, have the buckets been put in the same cups? I had some noise from my top end after all new cams and bearings were changed. I changed all the cups and it fixed the noise.

z1bman · #12 PostAuthor: **z1bman** » Wed Jun 08, 2016 9:20 pm

have you tried to pinpoint the noise with a stethoscope?

warren3200gt · #13 PostAuthor: **warren3200gt** » Wed Jun 08, 2016 10:25 pm

http://www.z1ownersclub.co.uk/forum/vie ... ht=#275058
This is the thread when i was trying to diagnose mine. Might give you some pointers?

#14 PostAuthor: **chrisu** » Thu Jun 09, 2016 7:30 am

thanks - looks like a few interesting things to check there.

Head is now in bits so I'm going to start with the oilways

#15 PostAuthor: **chrisu** » Thu Jun 09, 2016 4:21 pm

engine is now quiet.

happy (and relieved) bunny !!!

noisy top end after rebuild.

noisy top end after rebuild.

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