Smoking exhaust still - help!

[oldgreyandslow]

Its more a case of tools/time/ability

valve stems cost OK

I need to get a compression test first, so buy a tester or get a mech in?

That should tell me at least if the rings are fucked?

If stem seals I need to get the heads off, prob can do that

Then replavce seals, specialist kit, so mech again

Put lot back, OK could do that, then redo valve clearances?

Onto the exhaust/jet sizes:

I asked Rick what he'd recommend for a race can and also for one of his viper cans, he said 120/122 and that most race cans were alike so that would do whatever

Yes its std headers and std original can at the mo

I'm buying second hand rear headers and an ali unbranded can from a guy on here, basically to see how it goes and to avoid butchering my original stuff

[Dynamohum]

out of curiosity has bike been given a decent run on road and still smokes ?

[oldgreyandslow]

out of curiosity has bike been given a decent run on road and still smokes ?

Not really

60 miles on way back and 20 or so each time before it died

Making this a fuckin expensive £ per mile toy

[Dynamohum]

ok apologies sent i never read fullthread sounds like bike is about to get the basil fawlty treatment then. looks like you have done lots and its still coming the c--nt on you .. then can understand it being a ball buster. good luck on getting it sorted out.

[CMSMJ1]

You are still running std can and running it pretty rich.

You can check compression with a tester but you need an adapter for the 8mm plugs.

So...unless you are fitting a race can asap I would rejet it back to a standard setting of 115/118. I would also be tempted to let it get pretty hot 90+ to ensure all condensation is burned out of the system and the oil.

[Hadies]

I would also be tempted to let it get pretty hot 90+ to ensure all condensation is burned out of the system and the oil.

When I don't use my bike for 1 week+ it 'smokes' like a bitch and takes a while for the condensation to blow out of the system.

[Neosophist]

Standing bikes usually smoke 'steam' for a while as water condenses in the system.

Run your bike (put a block under the side-stand so its' level) and let the fan kick in and then shut off and then leave it running till the fan-kicks in a second time.. this will ensure everything is hot hot.

If your still smoking quite a lot then time to check valve stem seals and piston rings (engine out job for the piston rings and there not cheap)

Might be overly rich but it shouldn't smoke so much.

Let it get fully warm and give it a run down the road (hard).

The rough idle is indicative of piston rings if the carbs are properly set-up.

A compression test will tell you if you have leaky valves / piston rings etc (will need to be investigated further).

You can get a compression tester for about 20 quid but you need an 8mm adapter as Mark said to fit the NC30 plugs.

[oldgreyandslow]

Spoke to a bike mech yesterday and explained the situation and history to him, he thinks it may still be a carb issue, possibly knackered float or float height and suggested I check them. He also reckoned the reason the oil level may have looked high was because petrol was getting into it as the carb float(s) are out.

I hope he's right, I thought I'd checked them correctly before installation as per Haymes but maybe not!

So I'm going to remove the carbs yet again Saturday put the jetting back to standard give everything yet another clean and check the float heights.

Any other advice re float height setting appreciated, are there any tips on getting it jujst right? I did find the Haynes method a bit tricky.

When I cleaned the carbs last weekend I used Wynns carb cleaner spray, are there any better options? There seemed to still be a slight varnish like deposit at the very bottom of the bowls even after several hours of soaking, I did scrub away at them with a toothbrush though and the emulsion tubes cleaned up OK

Also I added a shot of redex into the petrol tank, maybe not a good idea.

Failing that its time to get the compression tester out, a guy I work with has one and he's happy enough to lend it but its one for a car so what is this adapter thing I need?

[Neosophist]

You'll need an 8mm adapter for the spark plugs

http://www.factorypro.com/tech_tuning_p ... edure.html

Have a read of this for the float height. I don't use their tool just a generic veriner caliper with a depth gauge.

If fuel was in the petrol you'd notice it when you drained it.

Hope that guides of some help

[porndoguk]

You'll need an 8mm adapter for the spark plugs

http://www.factorypro.com/tech_tuning_p ... edure.html

Have a read of this for the float height. I don't use their tool just a generic veriner caliper with a depth gauge.

If fuel was in the OIL you'd notice it when you drained it.

Hope that guides of some help

Edited for you :)

i too just use a vernier with the depth set to 6.8mm and then use the little dial to lock it off, carbs on there side and adjust till there spot on.

dont use REDEX, theres no need, the bike is to simple! and if youve cleaned it sensible it wont be doing anything other than wasting your money and making the fuel mixture shit.

this is the route the fuel goes,

Petrol Tank> Filter> Tap> Hose> Carbs> Tees Off x2> Float Valve Filters x4> Float Valves> Carb/Float Bowls>
JETS>
(pilots or Mains Depending on Throttle position)
Pilots> straight into the Venturi> Engine> Suck> Squeeze> Bang> Blow
Mains> Emulsion Tubes> Slide/Needle> Venturi> Engine> Suck> Squeeze> Bang> Blow

so as you can see you probally clean all these when you had the carbs apart, and if i remember REDEX does make your exhaust smoky so another posible cause.