edge of piston going well below exhaust port at BDC

[jonny snatchsniffer]

yes just use a sanding drum in the dremmel, how are the transfers at bdc ?

[tonydevon]

??? bleaurgh??? LOL thats what my brain just said in reply to that Question

I havent a clue what the transfers are.

I just applied the only bit of 2 stroke knowledge and logic that I have and noticed the exhaust port issue

my plan is to get it all put together and run in, learn to ride a scooter and then ship the motor to someone that can sort things like the ports out for me, right now I cant afford it. spent everything I had spare buying the project and rebuilding the engine, beginning to wish I had just put a new piston in the old cast iron 175 barrel and ridden it.

[Spanish Fly]

What about the lower edge of the transfer ports? Where are they in relation to the piston at BDC?

SF

[coaster]

??? bleaurgh??? LOL thats what my brain just said in reply to that Question

I havent a clue what the transfers are.

Simples, they are the ports that are fed from the crank case and 'trasnsfer' the charge to the combustion chamber as the piston descends. They should open at exactly the same time. As Eden says, using a sanding drum in a dremel shouldn't harm the nicasil.

[Darrell Taylor]

Id leave the ex port ,adjust the cylinder with gaskets or not to get the base of the transfer ports level with piston crown (when ex port is at 12 oclock the transfers are at 3 and 9 with the boost port at 6)
then set the squish to recommended setting via head gasket thickness

[tonydevon]

ok well I had the head off and measured the squish the way I was advised today by someone and also just found the method in the stickybook

squish is 0.8 so thats obviously too small, cant head gasket it as it doesnt run one, the head is stepped into the barrel on my mugello,so I reckon Im going to be putting another gasket in the base and then the exhaust port moves up another 0.4-0.5mmLOL

oh I would cry if it wasnt so cold and they might freeze

taken photos but tryingto get them onto this computer and online, no idea if they any good yet

[tonydevon]

pics of my kit at TDC and BDC, barrel off tomoro, probably double the base gasket, then test squish again. but that exhaust port is gonna go up another 0.5mm at a guess

[giankx]

On my RT240 (71bore 60stroke) the piston was below the exhaust port like your. I just checked the squish and it was really easy to set it up because it has a recessed head. The engine is really torquey end revs to 9000 rpm. I have done 5000km and no problems at all.

[giankx]

I could use silicon gasket instead of a 0,5 alloy gasket to have a perfect ports level, but the engine runs so smooth that i don't feel it necessary....

[Darrell Taylor]

cam lam show head gaskets for 7 stud kits at 0.3 / 0.5 / 0.65 and 1mm i presume there for your kit , i regularly run head gaskets on in/level/out type heads

if there for yours ,id remove the base gasket as all the ports are high and fit 1 of above to get desired squish