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Rebore SP1

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Robert View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Robert Quote  Post ReplyReply Direct Link To This Post Topic: Rebore SP1
    Posted: 11 Jan 2023 at 00:08
My SP is showing poor compression on both pots.
Perhaps new rings might improve things but is a rebore & oversize pistons possible, or is it the case of new barrels & pistons or even new sleeves .


Thanks
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#1moto-uno View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote #1moto-uno Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jan 2023 at 01:15
If you have access to a leak down tester, you will know what's necessary . It could be
tight valves , leaking head gasket or burned valves also . Peter
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ranton_rambler Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jan 2023 at 06:26
When I had a similar problem with my SP1000, I discovered that there are oversize pistons listed but I couldn’t find any.
I settled for a good secondhand barrel on the really bad side and new rings on the other.
As they are iron liners, it should be possible to get them replaced if you know somewhere competent.
Ian
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Brian UK View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jan 2023 at 07:48
First thing to do is check the valves are seating properly. Don't even think about rebores until you are certain those valve seats are perfect.
Brian.

Better 5 minutes late in this world than years early in the next.
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 11 Jan 2023 at 19:03
Originally posted by Robert Robert wrote:

My SP is showing poor compression on both pots.
Perhaps new rings might improve things but is a rebore & oversize pistons possible, or is it the case of new barrels & pistons or even new sleeves .


Thanks

How did this begin? Why did you do a compression test?



"Chicken nuggets don't dance on a Tuesday."
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