So, I'm in the process of putting my tracker together and just got my top-end buttoned up yesterday. Like a dumbass I forgot to install the red cylinder base o-rings. I'm trying rationalize and talk myself out of tearing the whole thing down again, 'cause I would really rather not; it's not just the time, but the Yamabond on the rocker carrier and the copper spray I used on the head and base gaskets. So I thought I would get some opinions.
It's been a while since this topic has been discussed... I did my best to use the search tool before posting, but didn't find a definitive answer. This is the best thread I could find:
https://www.xs650.com/threads/fit-new-o-rings-to-each-cylinder-spigot.5492/post-57196
I guess I have some reservations as to the o-rings' stated purpose.
The most common explanation is that they prevent oil from wicking up between the liner and the block casting and affecting heat transfer, but if there is a space wide enough for oil to get in there, then if there isn't oil, there must be air, and oil is better at heat transfer than air. "Fretting" could only be an issue if the liner is not constrained vertically, but there is a shoulder at the top of the liner that is held in place by the block and the head, so it can't go anywhere.
Or, maybe they're just there as an extra measure against leaks.
I guess I'd like to hear from anyone who has actual experience with this either way: like, "I left the o-rings out and my cylinder base leaks like a sieve" or "I left the o-rings out and my engine overheated and scored the cylinders", or "I've built a half-dozen of these motors without the o-rings and never had an issue".
If it makes any difference, this is not going to be a daily rider; I have bigger motorcycles that aren't 45 years old for that. This is a toy that will be lucky to see 30 miles at a time and 500 miles a year going to shows, bike nights, poker runs and doing wheelies in front of the house 'till the Chief of Police tells me to stop.
Thoughts?
It's been a while since this topic has been discussed... I did my best to use the search tool before posting, but didn't find a definitive answer. This is the best thread I could find:
https://www.xs650.com/threads/fit-new-o-rings-to-each-cylinder-spigot.5492/post-57196
I guess I have some reservations as to the o-rings' stated purpose.
The most common explanation is that they prevent oil from wicking up between the liner and the block casting and affecting heat transfer, but if there is a space wide enough for oil to get in there, then if there isn't oil, there must be air, and oil is better at heat transfer than air. "Fretting" could only be an issue if the liner is not constrained vertically, but there is a shoulder at the top of the liner that is held in place by the block and the head, so it can't go anywhere.
Or, maybe they're just there as an extra measure against leaks.
I guess I'd like to hear from anyone who has actual experience with this either way: like, "I left the o-rings out and my cylinder base leaks like a sieve" or "I left the o-rings out and my engine overheated and scored the cylinders", or "I've built a half-dozen of these motors without the o-rings and never had an issue".
If it makes any difference, this is not going to be a daily rider; I have bigger motorcycles that aren't 45 years old for that. This is a toy that will be lucky to see 30 miles at a time and 500 miles a year going to shows, bike nights, poker runs and doing wheelies in front of the house 'till the Chief of Police tells me to stop.
Thoughts?
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