Black smoke out of exhaust

[funmonkee]

...is black smoke on these icy damp cold nights normal after a 20 minutes run? The bike starts up fine and the fumes are clear on startup (in the morning), but when I get home after 6ish..the fumes are black... oil contamination? BTW its my 'max
____________________
**** Don't ride faster than your angel can fly Get this Free Space
The democratically elected Mod of the Scottish Section - The Peoples Choice[b]

[hazza]

if it were oil i would imagine you would be getting alot of white smoke with a distinct smell of oil, black smoke usually means your running mega rich
____________________
3 Honda NC50's(Sold)-->'72 Puch Maxi S (Sold, want it back!)--> '90 Yamaha RXS 100 (Stolen)--> '87 Honda Cub 90(Sold) --> '95 Kawasaki Eliminator (Sold) --> '98 Bandit 600 (Sold) -->'07 SV650S (Current)

[geordiecbrblo...]

^^^ what he said.

Black fumes are unburnt fuel, are you using a lot of petrol?

[funmonkee]

[Al]

Agree, yep black smoke is normally rich mixture.
Burning oil is normally blueish color smoke.
white smoke is normally steam/moisture.
____________________
Yamaha FZR400RR 3tj
My Instagram Thingy

[funmonkee]

Would that also explain why the 'max has stalled itself at lights twice last week (very embarrassed me:oops:).?. Also the power is just pants these days:down:; I seem to give it some throttle and wait a few second then it shots off like a cartoon character...not so great in town...nice out on the open bypass

cheers people
____________________
**** Don't ride faster than your angel can fly Get this Free Space
The democratically elected Mod of the Scottish Section - The Peoples Choice[b]

[finpos]

Hmm, worst case is your are getting compression in the crankcase due to leaky piston rings. Compression test will tell you if that is the case quickly enough

You can try to take a look at your oil level, also see if your airbox is full of crap.

finpos.

[funmonkee]

[funmonkee]

btw I've been losing alot of cooling fluid,,,can't find a leak I just keep topping up. about an two or three inch each week I've topped up the oil just in case. Am a bit scared of the whole breaking another engine thing
____________________
**** Don't ride faster than your angel can fly Get this Free Space
The democratically elected Mod of the Scottish Section - The Peoples Choice[b]

[finpos]

You'll need to take it to a bloke with a compression tester. The coolant loss may or may not be related, but comes under the general heading of "not good"

finpos.

[Paddy Blake]

Check if the choke cable is sticking on.

[funmonkee]

[finpos]

[funmonkee]

[finpos]

Thermostat is kinda important. What you might find is that removing the 'stat actually created short circuit in the cooling system, so all you did was to pump more, cooler water past the sensor (gauge now looks ok) while starving the engine of that very same cooler water, i.e. you overheated the engine even more.

Stat out is ok for diagnosis/bodging, I wouldn't run an engine I wanted to keep like that. Definitely not a fix for overheating.

finpos.

[funmonkee]

nuff said will probaby put it back in tomorrow. going to change oil/ filter etc and check a few other things.
____________________
**** Don't ride faster than your angel can fly Get this Free Space
The democratically elected Mod of the Scottish Section - The Peoples Choice[b]

[veeeffarr]

Have you checked the air filter isn't blocked?

[funmonkee]

History: the engine was busted a few months ago and got a full rebuild with replacement bits from my other fook'd max!!!

I've changed the oil once since the rebuild. So...

Tomorrow I go in search of

oil
new oil filter
check the airfilter
reinstall the thermos
check the mix of the fuel/air/carbs
choke cable no stickin
etc

will get back and update....

oh aye and i've got a slow rear puncture... joy


____________________
**** Don't ride faster than your angel can fly Get this Free Space
The democratically elected Mod of the Scottish Section - The Peoples Choice[b]