Topic: Boring Cylinder to 50 over

[WhyNot2]

It still has a ohc, but only one banger. CB100 tinker toy

Simple question I hope:::

When I have the cylinder bored and honed to 50 over the oem spec, will I have to do anything to the head?

Will the head gasket need to have anything done to it?

I'm only going 50 over because of the gouges in the cylinder wall.

Appreciate the help.

[MCRider]

It still has a ohc, but only one banger. CB100 tinker toy

Simple question I hope:::

When I have the cylinder bored and honed to 50 over the oem spec, will I have to do anything to the head?

Will the head gasket need to have anything done to it?

I'm only going 50 over because of the gouges in the cylinder wall.

Appreciate the help.

Head = no
head gasket = no. IF you think about it, the 50 over (.5mm) is a factory oversize. But Honda doesn't sell a factory oversize head gasket. Why? Becasue its not needed. A stock size gasket works fine. Should be new though.

[WhyNot2]

It still has a ohc, but only one banger. CB100 tinker toy

Simple question I hope:::

When I have the cylinder bored and honed to 50 over the oem spec, will I have to do anything to the head?

Will the head gasket need to have anything done to it?

I'm only going 50 over because of the gouges in the cylinder wall.

Appreciate the help.

Head = no
head gasket = no. IF you think about it, the 50 over (.5mm) is a factory oversize. But Honda doesn't sell a factory oversize head gasket. Why? Becasue its not needed. A stock size gasket works fine. Should be new though.

OK.....thanks for the quick response MC....dropping off the cylinder and piston at the machine shop today.

[MCRider]

YW. I got to thinking about it and Honda may have sold oversize headgaskets back when it was a current model. Memory fades... There's none shown on the fish now.

There's none listed for the CB750 stock oversizes.

They could be made by a gasket shop like Cometic.

Bottom line is for a .5mm oversize they are not needed.

[WhyNot2]

YW. I got to thinking about it and Honda may have sold oversize headgaskets back when it was a current model. Memory fades... There's none shown on the fish now.

There's none listed for the CB750 stock oversizes.

They could be made by a gasket shop like Cometic.

Bottom line is for a .5mm oversize they are not needed.

kewl........guess.....we'll see when I get it running.

[MCRider]

YW. I got to thinking about it and Honda may have sold oversize headgaskets back when it was a current model. Memory fades... There's none shown on the fish now.

There's none listed for the CB750 stock oversizes.

They could be made by a gasket shop like Cometic.

Bottom line is for a .5mm oversize they are not needed.

kewl........guess.....we'll see when I get it running.

I had a CT90 (The one with the deer rack on the back, canteen, flip up solo seat that covered the gas tank, handlebars that swiveled to inline with the frame so you could haul it closer on your RV)... I put a 110cc kit in it from Powroll. Men and their toys.

[754]

.50 over factory listing is very close to 20 thou or. 020..thickness of six hairs...no worries.

[WhyNot2]

Guess I've procrastinated long enough...........

Finally got the cylinder bored, just waiting for the gasket set to arrive.

Gonna start cleaning it up a bit.

[strynboen]

i have bored my yamaha to 1,50 and 2,00 over standart. find the pistons  is the problem..and hit the seitse..,0,04 milimerer tolerence