Working on cil.head - Your thoughts

[Mincehead]

Your valve faces and seats are safe,they are hardened steel and the wire wool will not damage them.

[Tarwetijger]

Here's an update while I'm having lunch.

This is how 'clean' it is right now. I'm not really convinced about the soda. It doesn't affect the alu though.
I got curious so left a strip of alu with soda on it for a night, this is what happened.

See the vague spot? That's all, and it's easily to rub it off with wirewool.

The wirewool works well to clear the carbon, but it's a lot easier if the carbon is soaked with WD40 or Wynn's injection cleaner, a tip I got from a mechanic.


The cilinderhead is not finished, meanwhile I'm putting the cilinders back on. I measured the piston ring end gaps at 0,6 mm. Standard is 0,3 to 0,45 mm, the official service limit is 0,7 mm. I decided to replace them anyway and the new rings actually felt tougher than the old ones. So it think it will make some difference.
The pistons are also cleaned with WD40, don't thy look pretty now?


I ordered a complete seal kit from KEDO. I expected some quality from the Germans but it appeared to be just an Athena set. Heard not such good things about those sets. What I hate the most about these things is that you never will be exactly sure that you pick the right O-ring.


Hm, Imagehost doesn't seem to work. Have to keep patience I think.
Well, lunch is finished so back to the garage!

[Killerwhale]

While doing rings i would hone the cylinders and run it in hard to seal them...
...and when putting it on, use a mate or a tool (could be the same) otherwise it´s a biatch!

[Tarwetijger]

While doing rings i would hone the cylinders and run it in hard to seal them...
...and when putting it on, use a mate or a tool (could be the same) otherwise it´s a biatch!

The cilinders are honed, and back on now. You're right, had to use a hammer very gently that is of course.
What do you mean run it hard? Like running in the engine?

[Killerwhale]

While doing rings i would hone the cylinders and run it in hard to seal them...
...and when putting it on, use a mate or a tool (could be the same) otherwise it´s a biatch!

The cilinders are honed, and back on now. You're right, had to use a hammer very gently that is of course.
What do you mean run it hard? Like running in the engine?

Yeah, running in the new rings hard....proven to seal better with lower oil consuption as a result.



....ps, i used both hands and a foot...will not do that again!!

[Mincehead]

Hey Tarwetijger,looking good.
The o rings should be easy to sort out,they generally fit into their respective positions snugly(good fit)but should not be deformed at all.
I`m sure you`ll work it out.Oh and yes as has already been said run those new rings in quite hard,it`s good to `bed` them in early on.Remember it`s not like running in a new/fresh engine.
New rings treated too softly can be a waste of time and lead to the same oil burning issues you had before.
I believe I`ve read it several times on the forum that TRX`s respond better to be run in a bit on the hard side,Steve certainly run his 878cc kit in hard if I remember correctly.

Ps;
Are you fitting a new cam chain while you`re at it?

[Tarwetijger]

Hey Tarwetijger,looking good.
The o rings should be easy to sort out,they generally fit into their respective positions snugly(good fit)but should not be deformed at all.
I`m sure you`ll work it out.Oh and yes as has already been said run those new rings in quite hard,it`s good to `bed` them in early on.Remember it`s not like running in a new/fresh engine.
New rings treated too softly can be a waste of time and lead to the same oil burning issues you had before.
I believe I`ve read it several times on the forum that TRX`s respond better to be run in a bit on the hard side,Steve certainly run his 878cc kit in hard if I remember correctly.

Right, I'll run it like I normally do then.

Cop: So mister Tarwetijger, speeding at 180+ km/h, do you think this is normal?
Tarwetijger: No sir, I don't think that's normal.
C: Then, why do you do it?
TT: I'm running in the engine, hard, because I've been told to do so.
C: Who told you that?
TT: Killerwhale and Mincehead!
C: Oh. Allright, carry on then.

Ps; Are you fitting a new cam chain while you`re at it?

No, I don't see a reason why I should. My bike only did 38.000 km.

[HansJ]

http://www.mototuneusa.com/break_in_secrets.htm

Controversial, yes, but I did this on my entirely rebuilt engine, and no probs so far.

[Killerwhale]

http://www.mototuneusa.com/break_in_secrets.htm

Controversial, yes, but I did this on my entirely rebuilt engine, and no probs so far.

..and i will hone and change rings and let them run it in on the dyno this spring so we´ll see what it will do to oilconsuption etc.
My GULPS oil as it is now...

[spookedbones]

http://www.mototuneusa.com/break_in_secrets.htm

Controversial, yes, but I did this on my entirely rebuilt engine, and no probs so far.

Did you use mineral car oil as sudgested?

[Baasm]

Hi Tarwe its looking good already. I wish I could help, with your questions...

Bye,ps post something in the dutch forum. Maybe are there some answers

[HansJ]

http://www.mototuneusa.com/break_in_secrets.htm

Controversial, yes, but I did this on my entirely rebuilt engine, and no probs so far.

Did you use mineral car oil as sudgested?

Yup, but changed quite soon to full synthetic.

I changed cam chain also, despite only having some 45000 kms on the clock. I am anal about engines, better to be safe than sorry, plus the timing was showing it was a bit stretched.

[Killerwhale]

http://www.mototuneusa.com/break_in_secrets.htm

Controversial, yes, but I did this on my entirely rebuilt engine, and no probs so far.

Did you use mineral car oil as sudgested?

Yup, but changed quite soon to full synthetic.

I changed cam chain also, despite only having some 45000 kms on the clock. I am anal about engines, better to be safe than sorry, plus the timing was showing it was a bit stretched.

...and as you know mine where 2,5 coggs out and tensioner only 3 clicks left...and that was under 40000km

[pbear62]

Hi guys, As I posted on here a couple of months ago, I had my cylinders honed & new rings fitted & replaced valve stem seals (using all genuine Yamaha parts) in October as my '96 model was using a bit of oil. I ran the rings in using Yamalube mineral oil for 800kms - didn't treat it too rough nor too gentle during this period. After running in I replaced oil & filter (still using Yamalube mineral oil) & have now just clocked over 4000km since doing this work & it hasn't used a drop of oil. Just replaced the oil & filter again yesterday & am still using the mineral oil - no reason to change to synthetic I reckon with these results.

[Tarwetijger]

Hi Tarwe its looking good already. I wish I could help, with your questions...

Bye,ps post something in the dutch forum. Maybe are there some answers

Ah well, those dutch guys don't know nothing...

I changed cam chain also, despite only having some 45000 kms on the clock. I am anal about engines, better to be safe than sorry, plus the timing was showing it was a bit stretched.

...and as you know mine where 2,5 coggs out and tensioner only 3 clicks left...and that was under 40000km

I didn't know that the cam chain was such a weak point? The marks on the cam lined up nicely with the cil.head though!
Will have a closer look on the cam chain then. Doesn't the engine case need to be split in two, to change the chain?

Hi guys, As I posted on here a couple of months ago, .... I reckon with these results.

Ah nice to hear (read) some good results. I'm hoping for the same of course!