Got myself an 05 TTR250 about 3 months ago and its got roughly 8500km on it. My issue is it seems to burn approximately 100ml of oil per 180km (1 tank of fuel). It doesn't noticibly smoke, however if I leave it idle then give it a rev I can see some bluish tinged smoke out the exhaust.
Is burning this amount of oil harmful and a sign of imminent failure? Any ideas what work might need doing?
Appreciate any help from guys more experienced with these bikes.
It seems to me that your TTR using lots of oil could be one of a few things.
If the bike has been laid up, unused, for some time then the piston rings could be gummed/stuck in their grooves - not in contact with the bore. This would allow oil splashed on the cylinder wall to stay there rather than being normally scraped off. Only a barrel removal and ring renewal will cure this, short of a rebore.
The other event could be looseness in the valve guides which allows oil to seep past the valve stem and be burned on the inlet stroke or ejected on the exhaust stroke.
Either way, it would be best to monitor the consumption to see if it gets worse, is static or gets better with time and use. If you could arrange a leak-down (compression) test then your culprit would be found quicker.
If the valve stems, or valve seals, leaked then it you would usualy see a discernible haze of blue smoke - becoming more evident on the over-run or as you decelerate. There is quite a volume of oil naturally present around the valve spring areas and oil seepage here is quite common. The stem steals are easily renewed.
Just removed my spark plug after a trip around France on the tet and the plug looks a bit oily to me. Can someone with more experience than me comment on my spark plug condition please.
I have ordered a budget leak down tester off eBay - not sure if it will be any good but thought it worth a try for £30. Suspect it's the piston rings as all the valve guides have been replaced very recently.
The engine is also showing signs of getting hot. I was actually expecting to get a lean looking plug when I removed it but instead I got this. Going to check my oil circulation too but in addition to all of the above I think my cyclinder casting has cracked and is leaking oil from between the fins .
How much oil are you burning? Is there a blue haze behind you? If burning oil has suddenly started after the top end rebuild I would maybe suspect valve stem seals not fitting properly. Plug certainly looks oil fouled. What sort of milage have you done on this piston/rings?
325s run rich on standard jets in my opinion. I am running mine on 48/140, and that's with the slightly better breathing Motad silencer and a mildly opened airbox aperture.
The only cure for the weeping fins is have the sleeve pressed out, then pressed back in slathered in Loctite "green". This worked for me despite being able to see the shiny sleeve through the crack! Maybe rehone to check nothing has warped during the process.
Not too bad on initial start up but puffs a bit of smoke on each quick blip of acceleration.
I had valve guides, seat and stem seals all replaced at the time of the 325 upgrade and that was a mere 2000 miles ago, 1500 of which were fairly relaxed off road miles on and off the yet, albeit in that horrendous heat wave in France two weeks ago!
Would I be correct in saying that if it was stem seals, any oil that leaked down whilst standing would burn off after each use and not necessarily leave the plug oiled up?
Cheers for the help! Really helps with the confidence to diagnose correctly.
Only a barrel removal and ring renewal will cure this, short of a rebore.
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