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Nc30 problem solving
Posted: Sun Mar 20, 2016 5:41 pm
by Barry1234
So, started strip down today to basically check everything is ok with bike, list of problems you guys might be able to help me with
1. Oil leak from both rocker covers, are these a diy job? Remove 4 bolts replace gaskets etc
2. Took of fuel tank, tap leaks even in off position, again is this an easy fix with Rick Oliver kit?
3. On tickover cylinder 3 exhaust was not heating up, plug looks ok, bike seemed to ride ok
Sorry for all the questions, seems I may have bought a lemon
Re: Nc30 problem solving
Posted: Sun Mar 20, 2016 5:46 pm
by bikemonkey
Are the rocker covers leaking or weeping?
Fuel tap kit should sort that.
How long had the bike sat not running before you discovered this? Mine was the same after it's winter lay-up but soon came good once I let it get proper hot

Re: Nc30 problem solving
Posted: Sun Mar 20, 2016 5:53 pm
by Barry1234
Cheers for reply
Rocker covers are weeping, bike has sat for months (I only bought it last week) went for a 10 mile ride earlier and all seemed OK, started bike in garage a couple of hours later the smoke starred pouring out from under seat/tank from oil on headers, wiped my hand across rocker join and fingers were covered in clean oil.
Re: Nc30 problem solving
Posted: Sun Mar 20, 2016 6:09 pm
by bikemonkey
New gaskets then. May also be worth looking at the rocker cover bolt holes, there's rubber grommet jobs in there that may have compressed too much over the years and are no longer allowing the bolts to put correct pressure onto the rocker cover gaskets to allow them to seal.
I think I have this problem with mine, I replaced the cover gaskets but they still weep slightly.
Re: Nc30 problem solving
Posted: Sun Mar 20, 2016 6:16 pm
by Barry1234
Cool thanks, will order parts
Re: Nc30 problem solving
Posted: Mon Mar 21, 2016 6:59 pm
by Barry1234
Think I've found problem, it appears when the shims were done last year they didn't apply gasket sealant and also left lumps of old sealer in rocker cover groove, but also found a split where gasket meets spark plug opening so needs a replacement anyway, also a little bit crusty in places
Re: Nc30 problem solving
Posted: Tue Mar 22, 2016 7:32 am
by Malc
Barry1234 wrote:Think I've found problem, it appears when the shims were done last year they didn't apply gasket sealant and also left lumps of old sealer in rocker cover groove, but also found a split where gasket meets spark plug opening so needs a replacement anyway, also a little bit crusty in places
You shouldn't need gasket sealer with a new gasket and everything clean before refitting.
Re: Nc30 problem solving
Posted: Tue Mar 22, 2016 9:36 am
by Barry1234
ok thanks
Re: Nc30 problem solving
Posted: Tue Mar 22, 2016 1:26 pm
by Neosophist
Malc wrote:Barry1234 wrote:Think I've found problem, it appears when the shims were done last year they didn't apply gasket sealant and also left lumps of old sealer in rocker cover groove, but also found a split where gasket meets spark plug opening so needs a replacement anyway, also a little bit crusty in places
You shouldn't need gasket sealer with a new gasket and everything clean before refitting.
you apply gasket sealer to the cut out sections only.
each side there are "u" shaped cutouts. these have sealent in them.
its all in the service maunal in the downloads section
Re: Nc30 problem solving
Posted: Tue Mar 22, 2016 1:51 pm
by Barry1234
thanks I shall download now