TB v2 race head upgrade?

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Update... I have finally put the v2 on my new 160ho, pretty sure I've got every thing sorted. I decided to go with an oko26 I dont have a 40 pilot so will try with a 41 and 108 to start with.

Is there any way to make sure that I havn't got the timing out by 180deg, with the plug out I can turn the motor over by hand on the flywheel and doesn't feel like anything touching valve/piston.

Also can't get a hold of any full mineral oil at the moment so was wondering if this oil will be ok to run the new engine in?

I checked the castrol website and it does say that it is good for wet clutch's

What do the pro's think??

I use that oil in all my bikes and never had an issue.
 
I've been reluctant to fire it up since it is the first time I have changed a head on these things but finally bit the bullet today and started it up and started running it in. Took a while to fire into life but once it did it seemed to run smooth, idle was a little high and getting used to the de-comp button as it pops out every kick.
Ended up starting without the choke. Before I put the oko26 on I rejetted it with a 41 pilot and 108 main and wound the air screw out 1.5 turns.
It runs pretty good like that at the moment, no hesitation or bog. Time will tell once I can start working the engine a bit more.
Its hard to tell the difference the v2 head makes at this stage but the higher compression is noticeable.

I should have a tank of juice through it by the end of the day and start revving it out a bit more.

I've put about half an hour on it and it's running good so I presume I got the timing and valves correct, cant hear any knocking or bad noises.

There does seem to be a bit of a vibrating noise coming from the head at times, is this just the roller rockers? Almost sounds like something is loose, I checked the valves and they are tight(had the lock nut come off completely on intake valve and found it sitting in the exhaust valve cover) on my other bike! haha

I will update whether its still going by the end of the day. haha
 
You will definitely notice the difference when you ride it. Also it will rev higher before limiting. Make sure you use the decomp button and kick from TDC. The compression WILL crack your kickstart gears if youre not careful. Im pretty sure that vibrating noise is normal. Is it sorta like a whirling noise?

Sent from my HTC 2PS6200 using Tapatalk
 
Got about 2hrs on the new v2 now and starting to give it a bit more of a workout. I think I might be falling in love with these v2's!! haha
Did a plug chop and plug looked a bit lean so I dropped the needle 1 clip and took it for another spin, it still performed the same(flawlessly), no bog or hesitation anywhere in the rev range, if I snap the throttle on quickly it responds instantly.
So I did another plug chop after dropping the clip and plug still looks a little lean.

I dont know whether I should go up a size on either of the jets, it's currently got 41 pilot,108main clip 2nd from bottom and air screw 1.5 turns out.

I'm using irridium plugs and find them a little harder to read than the standard ones.

The white porcelin part has slight colouration to it but not quite coffee tan colour.

The bike starts good 1st,2nd kick but only without choke, It wont start with the choke on.

I have a 42 pilot and a 110 main, suggestions please??
 
I would leave the pilot jet alone, or go to a 40 maybe, but not bigger. Try the 110 main jet with the clip back in the middle and go from there.

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