So .. was that 'tuned' head on Ebay worth it??

Greg · Post by **Greg** » Sat Nov 08, 2008 7:28 pm

Dunno - it's got 30 mins to go and it's at Â£195 .... be interesting to see how much it actually sells for and if it's really worth it..!

I've got a spare head that's in the winter overhaul plan - will it be worth getting the Dremel out?

Greg

steve speed · Post by **steve speed** » Sat Nov 08, 2008 8:10 pm

well head went for Â£195, and it would have to be in very good nick for that sort of money,, what was a surprise was the barrels and pistons Â£180 ,,,its Â£400 for the pistons and a rebore from TTS , so if they are JE pistons and i think they were that was a bargain

steve speed · Post by **steve speed** » Sat Nov 08, 2008 8:34 pm

Greg wrote:Dunno - it's got 30 mins to go and it's at Â£195 .... be interesting to see how much it actually sells for and if it's really worth it..!

I've got a spare head that's in the winter overhaul plan - will it be worth getting the Dremel out?

Greg

this is what i managed in about an hour

ive since cleaned it up some more , lapped the valves in,, fitted new stem seals, rebuilt the head and done the shims

Greg · Post by **Greg** » Sat Nov 08, 2008 9:27 pm

Nice one Steve ... It's be interesting to hear from anyone else who's worked on their own head rather than having it done, how easy it is, whether a flapwheel on a flex-drive can do the job or if you need to use a die-grinder or something....

Vince made quite a thing about the valve seats being triple cut - does that make any real difference?

G

Quan-Time · Post by **Quan-Time** » Sun Nov 09, 2008 11:40 am

pro tip:
280 grit "wet rub" / "wet and dry" / whatever you want to call it..
cut off a thin strip, about the width of your finger.
In and out motion on the floor and roof. So it has the lines going in and out, rather than side to side in a port.

Artsi_L · Post by **Artsi_L** » Fri Jan 09, 2009 1:39 pm

steve speed wrote:well head went for Â£195, and it would have to be in very good nick for that sort of money,, what was a surprise was the barrels and pistons Â£180 ,,,its Â£400 for the pistons and a rebore from TTS , so if they are JE pistons and i think they were that was a bargain

---

I can confirm. They are JE PISTONS. Sadly they were not 91,50mm overbore as I expected, but I'll get by with mere 0,5mm overbore as they are. That'll net me 859cc's.

I wonder what compression ratio this will net me. It's a hassle to do the hands-on-measurements.
Anyone know the compression ratio of these domed JE PISTONS?

cheers, A

steve speed · Post by **steve speed** » Fri Jan 09, 2009 2:28 pm

iam pretty sure they are 11 to 1 ,,,pity its not the 878 kit

Quan-Time · Post by **Quan-Time** » Tue Jan 13, 2009 2:54 pm

stock and JE replacements are rated at 10.5:1.

I have a set of 12.5:1 907cc pistons sitting here next to me.. (thats spare set, min order is 4 pistons when you get direct from JE)

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So .. was that 'tuned' head on Ebay worth it??

So .. was that 'tuned' head on Ebay worth it??

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Re: So .. was that 'tuned' head on Ebay worth it??

Re: So .. was that 'tuned' head on Ebay worth it??

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Re: So .. was that 'tuned' head on Ebay worth it??