Engine overhaul : What to replace ?

[Vilike]

Hi again.

I have to replace the starter clutch on my 1200.
  If i set the engine apart i want to replace everything thats need to be replaced of course. So the question is what to replace ? What to expect ?
  The bike is in good condition. Runs great. I bought it secondhand in 2010 with 117000Kms in the tachometer. She is from Italy.
  Details :
    Type : 1TX
    Year : 1986
    Mileage : 143000 Km
    Consuption : 5-7L
    Motor oil : only Castrol Actevo 20W50 in the last 9 years, replaced by every 6000Kms.
    Parts replaced : nothing except the Valve Cover gasket at 138000. The engine itself looks like it was never dismantled.

I expect to replace both chains and the starter clutch. But what could also be worn ?
    ThanX guys !

[Pat Conlon]

Sounds like a well cared for FJ, with the engine warm, what are your compression numbers?

Along with the 2 chains  (cam and starter) on the '86 I would plan on upgrading your 3 shift forks.

Replacing the oil jet on the starter chain with the upgraded shorter XJR version will help prevent future starter chain rattle.

I discovered some bad scratches and dent in the oil jet nozzle. It is the inside of the starter chain the toothed side that has hammered the nozzle.

Rolf, I just look at the starter nozzle photos and that is not very bad damage compare to others I have seen. Yes the chain gets enough slack to bounce around and contact the starter nozzle.

At some point (2006-2008ish) in the XJR1300 life span of the engine Yamaha address hard starting cranking issues specifically related to the EFI models. They changed the tooth count of the starter clutch reducing it by one tooth. That increased the torque on the crankshaft to help hard starting issues. That in turn required a shorter starter drive chain. The stock nozzle is 39mm long and the replacement is 21mm long.




The smaller diameter of the start drive gear and small chain meant the chain was now much closer. That meant as soon as the chain stretched, the chain would contact the nozzle. After many, many nozzle failure where it would get torn off and caught in the chain, with the result being a broken chain. Yamaha issues a recall and replacement nozzle.

I have both nozzles in stock, I have used a bunch in my race engine builds where we see the most chain stretch.

Randy - RPM

[Vilike]

Thanks Pat.

I don't know the compression numbers yet. We will take the look at those just before the dismantling.

We will upgrade the sift forks too of course.