Fred Head Questions

I was wrong, I thought the total for the bearings I ordered was $16, but that's not including shipping. It's $28 total. So for $10 more I could get one of the 15mm length ones instead of 2 of the 12.5mm Wiseco ones. I don't plan on increasing my performance to reach more than 7000rpm on flat roads, so I don't think I need the 15mm bearing as much as if I'm going up to like 10,000 rpm or whatever. But I am definetely curious what that extra 2.5mm does @Street Ryderz. You said in this post Which Molassi Piston Rings? that the 10×14×15mm piston needle bearing picks up the slack on end play. If I had to guess that means less wear on the snap rings or less wear on the bearings themselves or both??
 
@HumanPerson you said I should chamfer the edge of the transfer ports that are closest to the intake. Here's how the transfers look like in my old cylinder vs new cylinder
95682
vs
95683

The intake is on the right in both pics. As you can see in my old cylinder transfers (which don't exactly look beautiful 😆,) the right and upper edge have a slant to it. Should I try to recreate that on my new cylinder transfers and then round out ALL of the edges slightly? And what's with the barrier that separates the transfer openings into 2? There's also a post in the middle of the exhaust port. Should I get rid of that in the exhaust?
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@HumanPerson you said I should chamfer the edge of the transfer ports that are closest to the intake. Here's how the transfers look like in my old cylinder vs new cylinder
View attachment 95682vsView attachment 95683
The intake is on the right in both pics. As you can see in my old cylinder transfers (which don't exactly look beautiful 😆,) the right and upper edge have a slant to it. Should I try to recreate that on my new cylinder transfers and then round out ALL of the edges slightly? And what's with the barrier that separates the transfer openings into 2? There's also a post in the middle of the exhaust port. Should I get rid of that in the exhaust?
View attachment 95684
You definitely want to clean up and champher those edge's,the post in the exhaust port is a bridge to stop the rings from over extending into a wide or widened port but now with the sleave it's useless so can be removed.The transfer window/port edges should be done aswell and redirecting the wall closest to the intake's angle is what should be done.
 
I had to redirect the exhaust side of the transfers to blow towards the intake side, there was alot of cross talk which the redirection of the transfers fixed.

Used JBWeld.
@Street Ryderz explained to me what that was about ;)
 
Wow I didn't know jb weld would hold up in that. What kind of jb weld? Just the original stuff?
 
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The first cylinder i used the underwater jbweld lol

That cylinder is on another bottom end i had laying around and the second cylinder is what is on the bike with the broken frame now.
I used the high temp jb weld for that one and it is stil going, or would be if the frame wasn't broke :D

I used some fine wet dry sand paper and just used my finger to make sure the intake, exhaust and the two transfer ports had no rough edges that
the rings could catch, well worth the effort.

Smooth flow = you with a smile :p
 
When I'm rounding out the edges in the jug area, how fine of sandpaper should I use? Are we talking 400 grit or like 1000 grit. Or should I use 400 first and work my way up? Thanks
 
One last thing for now and I think I got a really solid understanding... I drew a red outline and blue outline in this picture of one of the transfer ports. When I chamfer it to make it flow more towards the intake, am I taking off material from just the red section, or both the red and blue? The outlines aren't perfect dimensions, its just so you get what I'm trying to ask. Basically am I gonna dig into the actual port (blue) or just the "sleeve section" (red.)
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