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off the top or bottom

Posted: Tue Jun 16, 2009 10:05 pm
by YAMLAM
i`ve had 1.5mm machined off the base of my TS1,due to indian caseing , Rd400 Rod, yam piston combination.using a MB .5mm gasket, i still have a .5mm neg deck height,should i remove it off the base or the top of the barrell.
What is the standard height of a TS1 barrel ?
thanks.

Re: off the top or bottom

Posted: Tue Jun 16, 2009 10:07 pm
by sean brady scooters
101.5mm................ :D
why not ............just not use a base gasket..............?
use a sealer instead...................................
thats if of course you require piston to match barrel height at TDC.................
what head/squish measurements do you have or want to achieve.........?

Re: off the top or bottom

Posted: Wed Jun 17, 2009 7:27 am
by YAMLAM
i did think of doing away with the base gasket,but was told by the person who machined the barrel ( and built the crank) to always use a base gasket.
measured the squish at 1.72

Re: off the top or bottom

Posted: Wed Jun 17, 2009 7:42 am
by jonny snatchsniffer
squish a bit big so a .5mm base gasket will be just the job

Re: off the top or bottom

Posted: Wed Jun 17, 2009 8:42 am
by soullad
Did you initially want to take 1mm off the base of the TS cylinder to give it that "touring" tune but ended up taking 1.5 mm to allow for the height difference in Injun casings?
I know MB recommend the 110 yam rod and packing plates for folk who just want the above.
What stroke crank and piston you running by the way?

Re: off the top or bottom

Posted: Wed Jun 17, 2009 9:05 am
by YAMLAM
it`s a TS1 200, RD400 rod (115mm) Yam IT175 piston,Indian casing,deck height was minus 1.5mm when all bolted down with a .5mm gasket .(thats what i measured it at,using feeler gauges).as it`s still got a minus .5 deck height at TDC,i wondered if taking it off the bottom would lower the port timings to much, hence the question TOp or bottom.
incedently, just measured the barrel and it measures 100.11 mm using digital vernier calipers!

Re: off the top or bottom

Posted: Wed Jun 17, 2009 9:32 am
by Diablo
The answer to this question very much depends on what you want the motor to do,what gearing and pipe your running etc. If you already have 1.5mm off the base I would certainly think very carefully about maching anymore.
Before you do anything else I would measure your port hieghts and use Edens port timing calculator to work out your timings.
I've had it before where I've had to have a step machined in the head because I don't want to alter the barrel position any to get the squish right.

Re: off the top or bottom

Posted: Wed Jun 17, 2009 12:50 pm
by YAMLAM
the head has been profiled to suit the IT piston and has a 1mm "step".
i will be using a AF fresco exhaust.

Re: off the top or bottom

Posted: Fri Jun 19, 2009 7:51 am
by YAMLAM
decided to remove base gasket, squish now 1.57, gonna run with this for starters. Can always remove more metal later, but cant put it back as easy !