Page 1 of 4

Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 6:28 pm
by oldgreyandslow
Did a lot of work this week which may well be in vain

Bought bike two weeks ago, all seemd OK on ride back from sellers, next day had a reg rec problem, sorted that.

Didn't ride bike for a week, next time very poor starting and running, got it going went out and it cut out, twice. RAC bloke said dodgy fuel, it had been standing a year so possibly. Anyway got it going, get home and noticed lots of exhaust smoke, bluey white when revved.

Checked oil level, it was high, seemed the previous owner may have checked the level on the side stand

Anyway decided to do a strip and clean.

Drain oil and water, both fine no oil in water or vice versa

Did valve clearances, cleaned carbs as per Cammo's instructions, rejetted to suit race can which should be coming soon, so now have 120f 122r instead of Jap standard but still have old standard pipe on at the moment.

Fresh fluids, air filter and sub filter, new plugs

Start up and .................................

Still lots of bloody smoke when revved FFS!!!!

Runs rough couldn't hold an idle but after it got warmed up and some adjustment of the idle speed seems a little better.

Rough running maybe due to the jet sizes and standard can?

Also noticed the can has a small hole at the front so when smoke and blowing appeared at the front I thought it may well be knackered! I guess its a drain hole.

Anyhow, some advice on whats causing this and what I ought to do appreciated (Scrapping the fucker isn't an option its cost too much already and is also causing matrimonial distress!).

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 7:07 pm
by Delboy
Does the smoke stop when the moto's warmed up?

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 7:12 pm
by Hadies
What colour is the smoke?

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 7:40 pm
by oldgreyandslow
I got it fairly warmed up, just over 70, still smoking like a bastard when revved

Smoke is a bluey white, or if you like white with a hint of blue/grey

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 7:47 pm
by lizard821000
coolent leak?

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 7:56 pm
by vfrman
If it were a coolant leak, wouldn't there be oil in the water or vice versa? He said there wasn't. I would do a compression check. I am thinking rings or valves/guides. Have you checked the valve clearances?

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 8:28 pm
by porndoguk
vfrman wrote:If it were a coolant leak, wouldn't there be oil in the water or vice versa? He said there wasn't. I would do a compression check. I am thinking rings or valves/guides. Have you checked the valve clearances?
:plus:

Valve stem seals,
Piston Rings,

Also i would suspect that the jets you have used are a bit over kill for just a can,

im a little experiance in removing the carbs, so much so me and the carb rubbers are on first name terms as weve meet so much! im runnin 115 and 118 i have a yamamota rear manifold, Tyga Can, and polished/Bandaged headers, and even with 120 & 118 i was runnin crazy RICH,

what you and other seem to forget is cammos guide is based on setting used in australia, and also that the UK spec nc30 uses different carbs etc.

the full TYGA system is recomended by rick oliver to use 120s all round, so i would guess your runnin stupidly rich which will and could add to your smoking issues,

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 8:33 pm
by oldgreyandslow
porndoguk wrote:
vfrman wrote:If it were a coolant leak, wouldn't there be oil in the water or vice versa? He said there wasn't. I would do a compression check. I am thinking rings or valves/guides. Have you checked the valve clearances?
:plus:

Valve stem seals,
Piston Rings,
Bollox that sounds expensive!

Valve clearances checked Thursday

What do I need for a compression check, DIY or mechanic, cost wise? If its £50 for the tool and £40 for a mech to check it for instance

I assume its an engine out, head off job?

Sheite, I hate this fucking bike

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 8:41 pm
by oldgreyandslow
Just an addition regarding the jet sizes, I actually asked Rick O what he recomended, I did buy the new jets from him, and he told me to go with 120/122 for a race can, also the bike is a 1990 so Jap spec not UK.

Would the jet spec really cause the smoke issues alone, or is it most likely a valve stem seal/rings issue?

What gets me is that it wasn't smoking 2 weeks ago, I just can't get to grips with it going tits up in about 150km

Re: Smoking exhaust still - help!

Posted: Sun Jun 26, 2011 8:53 pm
by porndoguk
more like this bike hates you!

erm, valve stem seals £6.50 + Vat and postage each from DSS or £1.50 each from wemoto.

piston rings never done them before but youll need head and lower gaskets,

i know a pair of head gaskets are about £80 Delivered from DSS!

no it wouldnt cause masive smoke it would just be much more sooty,

also confused with rick recomending 120/122 for just a can? your still running on standard honda headers and rear manifold's?

what can do you have fitted?