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parrisw

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Finally getting back to some of my saws that are needing attention. Was a busy summer. Figured I'd get my 371 back together, doing a BB kit on it which I got from MCW. Real nice kit actually, the ex port has a anomoly which will come out just fine with the porting.

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Lower trans roughed in.

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I always rough in the lowers before machining just incase I have a little slip with the grinder, the machine work will take it out.

Now time to machine the cylinder and piston.
 
Great pics... who makes that degree wheel? I'm still using the printed paper wheel glued to a cd. That's a nice wheel... I'd love to locate one.
 
Thanks for the excellent pics, ParrisW.

Looks like it has the dubious dark ring at the top of the bore.

LOL, I was waiting for you to come comment on the dark ring!! Honestly I've never had a problem with it, and its never caused me a problem. Its a unhoned area IMHO, it'll be fine.

Great pics... who makes that degree wheel? I'm still using the printed paper wheel glued to a cd. That's a nice wheel... I'd love to locate one.

MR Gasket.

Thanks everyone else for the positive words.
 
Great stuff Will.

They are a really nice cyl. Shame that ex is tilted a little. Even the rings look like those supplied with the Bailey's kit.

Keep us posted with what final figure you get at the ex when your done mate.

:msp_thumbup:
 
Great stuff Will.

They are a really nice cyl. Shame that ex is tilted a little. Even the rings look like those supplied with the Bailey's kit.

Keep us posted with what final figure you get at the ex when your done mate.

:msp_thumbup:

Thanks AL. Yes I'll surely let ya know what the final #'s are.
 
It's unhoned because the ID is larger there, so the hone couldn't touch it.

Do you use lighting to illuminate the jug for your photos, or is that just the camera's flash ? Sure are crisp pictures.

Yes That's most likely why, you can't feel any ridge by finger, I'd like to put a bore gauge in
there and actually see if that's the case or not. Yes I use lighting for my pics, the flash creates shadows.
 
Good stuff Will.
As mentioned every single kit I got in had exactly the same "slight tilt" on the exhaust port. After asking around it sounds quite common.

It's unhoned because the ID is larger there, so the hone couldn't touch it.

I've had a number of kits where the "ring of death" can be easily felt with a fingernail. I just checked 3 more of these BB372 kits and it does indeed look like the top portion hasn't been honed - I cannot feel any difference with my fingernail. There is, however, a definate ridge that reaches a few mm in from the top which is common.
If you look closely at Will's 3rd picture a second "ridge" can be seen closer to the squish band. This is the one I can feel.
 
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Good stuff Will.
As mentioned every single kit I got in had exactly the same "slight tilt" on the exhaust port. After asking around it sounds quite common.



I've had a number of kits where the "ring of death" can be easily felt with a fingernail. I just checked 3 more of these BB372 kits and it does indeed look like the top portion hasn't been honed - I cannot feel any difference with my fingernail. There is, however, a definate ridge that reaches a few mm in from the top which is common.
If you look closely at Will's 3rd picture a second "ridge" can be seen closer to the squish band. This is the one I can feel.


Thanks Matt for the info. So far the top of these cylinders have not caused me any trouble.
 
Got the machining done today after work. .030 popup. The only thing I dont like about these kits pistons is that they don't have as much crown thickness and OEM and Meteor pistons. It was only .120"

Sorry for the crappy Phone pics.

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Haven't done anything on the saw this past week, been playing with my Lathe, I bought a milling setup for it, so have been waiting to set it up for milling in piston windows in 372 pistons. Here is a couple pics, this piston is just a 372 piston, not the BB piston for this 371, that's next.

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Hey good job there Will! :msp_thumbup:

I checked out the kits I have here and yeah, the same as yours mate. I will be doing one for Matt so I'll leave the duration on the inlet a little lower to see how the exhaust and compression turn out in case it needs a spin.
 
Hey good job there Will! :msp_thumbup:

I checked out the kits I have here and yeah, the same as yours mate. I will be doing one for Matt so I'll leave the duration on the inlet a little lower to see how the exhaust and compression turn out in case it needs a spin.

Cool, ya they are a nice kit otherwise. I turned down the cylinder as much as I could, about .075-080", .030 popup.
 

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