Well, as mentioned the engine had to come out to check the barrel.

And it was like I expected, one of the older helicoil threads pulled out, so will give it to SERCO again and get him to try and fit a new thread/plug or whatever they need to do. The head certainly leaked as you can see, so it was time to have another go at it - one of the bolts was only hand tight... no wonder it leaked!

While I was at it, I also changed the main jet from #130 down to a #125, seemed to run a bit fat. What jet combination to others ride with? Got a #125 in the secondary carby, now also a #125 in the primary one - is that normal for Australia?





Once the barrel is beck from repair, I hope she will run a tad faster... let's wait and see.

Sven

I have never been a fan of them helicoil thingys, my late father did this for a living for almost 40 years & never installed a single one, he said they are useless.

Better to mill out & weld a plug inside, then drill & tap again (as good as new).

Mezo.

Mezo wrote:Better to mill out & weld a plug inside, then drill & tap again (as good as new).

Mezo.

+1

Helicoils should be ok in steel but aren't long enough for alley, specially when torque is involved.

Rick

xtzrick wrote:

Mezo wrote:Better to mill out & weld a plug inside, then drill & tap again (as good as new).

Mezo.

+1

Helicoils should be ok in steel but aren't long enough for alley, specially when torque is involved.

Rick

Helicoil's come in 5 lengths, for different applications, these are designed to be used for standard bolts, not for specialist bolts or for high torque bolts. A helicoil should never be used for cylinder head bolts, exhaust studs etc, for these areas, there a quite a few specialist inserts ie, "keysert" is a commonly recommended insert. The best repair will always be remove the damage, weld and re-tap, or replace the offending part

Rod

Well gentlemen, you be glad to hear that the offending stud has been plugged and drilled and tapped. So the engine is all back together (even used genuine gaskets... after using some made in Asia kit last time) and running much nicer and is leak free.

Still not sure whether the reduction to the 125 jet was right, but I will ride like this for a while and see what the plug looks like.

So, all good to go!

Nice one Sven, where did you buy your OEM gaskets & how much were they?

Mezo.

Never cheap those things from the Yamaha dealer: They were both about $80 each for the head and the barrel gasket.

Aussiesven wrote:Never cheap those things from the Yamaha dealer: They were both about $80 each for the head and the barrel gasket.

Well never cheap from an Australian Yamaha dealer Sven, if you got them from Partzilla the head gasket would be $45.00 & the base on a mere $9.50

Mezo.

Good to hear it's back together again Sven Interesting to see how it runs with the different jetting? Is your exhaust system stock or modified?

Exhaust is a "standard" SEBRING aftermarket exhaust that was available in the 80s in Germany... so that's the one the bike always had on and ran well with for years. was thinking to hunt for an original one day as I like the sound better...

Mezo, agree elsewhere they might be cheaper, but was in the usual... "can't be bothered and go next door to the Yamaha dealer" mood as I wanted to get it done, so you pay more, but hey it's only money, isn't it?

Sven