Re: head squish
Posted: Tue Mar 03, 2015 9:02 am
Out of curiosity what's the casing you're building this on?
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head squish
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Re: head squish
Posted: Tue Mar 03, 2015 11:48 am
Spanish
Re: head squish
Posted: Tue Mar 03, 2015 12:00 pm
Its a long shot but just check your barrel spigot isnt catching on your mag flange and not seating correctly I had this when I was building a rapido into a new 200 casing and used li 150 internals side case and mag flange as a doner just a thought , also if youuse the 60mm crank your squish will be .9 and you will adjust using gaskets ? You will need to check your piston crown in relation to the lower part of the exhaust port as itmay be to low but thats not always bad but iguess you know that
Re: head squish
Posted: Tue Mar 03, 2015 12:34 pm
thanks on reply Shocky
mag flange is fine, all bolted down nicely.
piston at BDC is flush with bottom of exhaust port
mag flange is fine, all bolted down nicely.
piston at BDC is flush with bottom of exhaust port
Re: head squish
Posted: Tue Mar 03, 2015 2:10 pm
right lads
me mates gonna take barrel to work & the machinist gonna do it.
so before he picks up tonight? am i fine to ask him to remove the needed amount say 0.7mm to give me a final squish of 1.2mm
& then away i goooooo
me mates gonna take barrel to work & the machinist gonna do it.
so before he picks up tonight? am i fine to ask him to remove the needed amount say 0.7mm to give me a final squish of 1.2mm
& then away i goooooo
Re: head squish
Posted: Tue Mar 03, 2015 2:50 pm
In my very limited knowledge,I would of thought you`d need to check your port timings first as it might need the base skimming( probably talking out of my ar5e again). I would certainly give Mick a call before you touch it and seek his advice.
ove
ove
Re: head squish
Posted: Tue Mar 03, 2015 3:31 pm
good shout m8,ove wrote:In my very limited knowledge,I would of thought you`d need to check your port timings first as it might need the base skimming( probably talking out of my ar5e again). I would certainly give Mick a call before you touch it and seek his advice.
ove
just rang & left him a message
Re: head squish
Posted: Tue Mar 03, 2015 11:44 pm
Another option would be to have the head machined (if possible) to drop down into the cylinder like the BGM RT/Avanti kit maybe.
Re: head squish
Posted: Wed Mar 04, 2015 10:46 pm
It'so not unknown for Indian and some Spanish cases to have a gasket face which is higher than the Italian standard. Which can contribute to this sort of issue.
Re: head squish
Posted: Wed Mar 04, 2015 11:02 pm
cheers on all the replies lads
Mick rang me back & i told him i have squish at 1.9mm .....
he says that is safe to run as i was worried about pinking(detonation) & if anything he suggested if i wanted? to taking a slither off the head with it being off a previous 67.2mm bored setup & this is running 66.6mm piston.
he has told me to run it & see after its all ran in how it performs...
i have got 2hrs on his dyno off him included in the price of the tune, so i will be down there at the earliest opportunity.
cheers
Mick rang me back & i told him i have squish at 1.9mm .....
he says that is safe to run as i was worried about pinking(detonation) & if anything he suggested if i wanted? to taking a slither off the head with it being off a previous 67.2mm bored setup & this is running 66.6mm piston.
he has told me to run it & see after its all ran in how it performs...
i have got 2hrs on his dyno off him included in the price of the tune, so i will be down there at the earliest opportunity.
cheers