Re: Suzuki GS150R

From the symptom you mentioned I quite suspect the right TDC was not set.

For our 4-stroke engine Top Dead Center(TDC) will occur twice in one combustion cycle. i.e. you will be able to see the 'T' mark twice in once combustion cycle 1) at the end of compression stroke 2) at the end of exhaust stroke. You want to set your valve clearances at the end of compression stroke (When both valves are closed) and not exhaust (When exhaust valve might not be fully closed)

See four-stroke engine Wikipedia for a nice animation.

Try the entire operation again with addition of a small check as below:
1) Ensure 'T' mark visible in the magneto cover inspection window
2) Move the valve tappets by hand and notice the play
3) Rotate the crank by 360 degress till you see 'T' mark again
4) Move the valve tappets by hand and notice the play.
5) If the play in step 4 is more than that in step 2 continue with adjusting the gap to suitable value now.
5) If you feel play was more in step 2 than that in step 4, rotate the crank by 360 degrees again and continue adjusting the gap to suitable value.

Recommended valve clearances
Intake: 0.04-0.07 mm
Exhaust: 0.10 to 0.15 mm

P.S. Valve clearance adjustment should be done in cold state only.

Re: Suzuki GS150R

For the first time as in DIY or bike's service life?
Did you perform it on cold-engine(off for over say 5 hours)?
I assumed that clearances increase over period of usage/service. How come your's were so tight/close?

Intake : 0.05 mm
Exhaust : 0.12 mm
are nominal I suppose.

Ride the motorcycle for 20 kms to give it a proper warm-up then check for the noises.


@rsk_kelkar did it a few months ago.

Re: Suzuki GS150R

Adjusted the tappet gap for the first time in 44K Kms.

Input was changed from 0.04 to 0.06
Output was changed from 0.06 to 0.09

Now the noise seems to be increased. My bike sound like the timing chain has worn out all of a sudden.

My question: is 0.06 & 0.09 not an acceptable setting for GS ?

I made sure that the "T" mark was visible on the inspection window while rotating the crankshaft and also the tappets had some play (TDC of compression stroke).

Apart from the play, how do we ensure that the we are adjusting the tappet clearance during the compression stroke ? Any visible identifications on the cam chain sprocket ?

Re: Suzuki GS150R

Replies inline in blue.

Re: Suzuki GS150R

Got my bike after Stator coil replaced. The part cost was 800 INR. Altogether including oil change, the bill came to 1600 INR.

1. What type of Engine oil do you guys prefer for your GS ? Any specific oil that is good ?
2. What could be the cause of Stator coil failure ? In most forums, I learnt that the life of this coil comes to 1 Lakh kms.
3. My another problem is the cylinder and piston is weak. So keeping a tab on the Engine oil level weekly.

All these things happening on a ~40k run 1.5 years old bike.