HI guy im new to this forum , but i hoping someone might be able to help. I have just put a takegawa 110 big bore kit into my old 90 , still running a stanard head and a 26mm mikuni carby . The issue im having is im getting a small amount of oil in the intake , it seems to by some sort of blow by . Ive pulled it down twice and inspected everything and i could find anything that could be causeing this issuse. Sorry i forgot to mention that im running a honda 106 piston , which is the same ( 52mm ) , i run a semi synthetic and im thinking of changing it to a mineral oil and see how it goes . Has any one else came across a similer thing.
TTR 90 big bore problem
- Thread starter ttr90man
- Start date
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DHZ_XR8cing
Master Spanner Spinner
Is the bike running ok apart from the oil problem?
Does it blow any smoke?
I will throw a few ideas at you.
Have you check the valve's to make sure they are seating and the clearance is ok?
Change valve stem rubbers?
Not over oiling the air filter?
Is the engine crank case breather not blocked at all?
Does it blow any smoke?
I will throw a few ideas at you.
Have you check the valve's to make sure they are seating and the clearance is ok?
Change valve stem rubbers?
Not over oiling the air filter?
Is the engine crank case breather not blocked at all?
HI the bike runs fine apart from the oil issue . It will blow a small amount of smoke if you are riding it hard for a while ( seems to be only on the down rev , if you no what i mean ) and when i have pulled the intake off i have noticed the oil , as for the valve seats , i havent checks but before the big bore kit , the motor was spotless internally , not a mark on the standard piston . checked crank case vent all good there. Runinng a pod filter and no its not oil from the filter , it engine oil ?
HI the bike runs fine apart from the oil issue . It will blow a small amount of smoke if you are riding it hard for a while ( seems to be only on the down rev , if you no what i mean ) and when i have pulled the intake off i have noticed the oil , as for the valve seats , i havent checks but before the big bore kit , the motor was spotless internally , not a mark on the standard piston . checked crank case vent all good there. Runinng a pod filter and no its not oil from the filter , it engine oil ?
DHZ_XR8cing
Master Spanner Spinner
Do you have any pics you can post of you induction set up??
The honda seem to be the choice of bike , the 90 is a good little bike , the only reason i went this way is because i already had the 90 and the big bore came about so i could keep up the the chinese bikes , as much as that dosent sound right , but some of those things motor
DHZ_XR8cing
Master Spanner Spinner
What hoses run to the manifold and carbie?
DHZ_XR8cing
Master Spanner Spinner
I was just making sure there was no funky hoses running to it.
Hows the plug look?
Do you run anything in your fuel?
Hows the plug look?
Do you run anything in your fuel?
The plug looks a little rich , but thats how i set it , and nothing in the fuel , only run BP ultimate? Im out of ideas to , thinking ill do a compression test tomorrow and just see if it brings anything up . I dont think it would have anyhting to do with runnig a honda 106 piston .
just because it is pressure does not mean its blowby... the piston is a pump and on the bottom of the piston also pushes air around.. therefor making crankcase pressure
there should not be blowby unless you installed it wrong.. (no rings or somthing) other than that it should have a perfect seal
if there is nothing else you can find i would consider replacing my valve stem seals after that there is nothing else that could be wrong.... unless you have a tear in your head gasket between the oil hole and your combustion chamber but that is unlikley
DHZ_XR8cing
Master Spanner Spinner
If the bike is running ok and not blowing smoke I wouldnt be too concerned about it
Ive just done a compression test and it has 125 psi , the manual states for 145 standard , im thinking the compression is down a little due to the size differance in the 106 honda piston , the 106 piston is not quite the same size at the top of the cylinder.
that means it has a higher pin height...
yeah that sounds about right... if you have bored it and honed it with a new piston and rings then a compression test was not needed...
besides ride the damn thing untill it smokes too much it may just be the rings bedding in also so ride her nice and hard
