rebuild compression issue
- Two_stroke_brit
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rebuild compression issue
Hi All, i got this 98 220R as a basket case.
i checked the compression and it was showing about 80 PSI.(carb and pipe removed)
i checked the bore with a good gauge and was showing a little small if anything, and no scores or damage.
So took the top end off and replaced the piston with a wiseco , and rebuilt it.
i have had the reeds out and look ok and seem to lie nearly flat all over.
now retested and still only around the 80 mark.
am i missing some thing obvious .
i am going to do a leak down test next.
thanks mark
i checked the compression and it was showing about 80 PSI.(carb and pipe removed)
i checked the bore with a good gauge and was showing a little small if anything, and no scores or damage.
So took the top end off and replaced the piston with a wiseco , and rebuilt it.
i have had the reeds out and look ok and seem to lie nearly flat all over.
now retested and still only around the 80 mark.
am i missing some thing obvious .
i am going to do a leak down test next.
thanks mark
she might be older but still a fun ride.
- bufftester
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Re: rebuild compression issue
If it's low compression I would start by squirting some 30W oil in the top end and rechecking. Could be the cylinder is out of round not allowing the rings to seat well. Assume you checked the head for any cracks or anything when it was off. Also check for good seal between the head and cylinder to make sure you have no leaks there.
- Two_stroke_brit
- Supporting Member I
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- Joined: 07:18 pm Sep 09 2020
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- Location: Hockley TX
Re: rebuild compression issue
thanks for the pointersbufftester wrote: ↑03:20 pm Apr 10 2021 If it's low compression I would start by squirting some 30W oil in the top end and rechecking. Could be the cylinder is out of round not allowing the rings to seat well. Assume you checked the head for any cracks or anything when it was off. Also check for good seal between the head and cylinder to make sure you have no leaks there.
will do ,
leak down test should tell more.
thanks mark
she might be older but still a fun ride.
- Two_stroke_brit
- Supporting Member I
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Re: rebuild compression issue
bearing in mind i got this as a basket case with unknown issues
well did the leakdown test and as fast as i pump it in its pissing out .
looks to me like the crank seals are toast.
should of done the leakdown test first (lesson learned)
cheers mark
well did the leakdown test and as fast as i pump it in its pissing out .
looks to me like the crank seals are toast.
should of done the leakdown test first (lesson learned)
cheers mark
she might be older but still a fun ride.
- KDXGarage
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Re: rebuild compression issue
Oh well. Good luck on the rebuild.
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- Two_stroke_brit
- Supporting Member I
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- Location: Hockley TX
Re: rebuild compression issue
Well rebuilding now new crank bearings and all new seals all round.
still having issues with compression # and leak done testing .
on closer inspection i think the reeds may be toast too.
what do you think.
Worn out reeds by mark.dobson, on Flickr
as always thanks in advance.
Mark
still having issues with compression # and leak done testing .
on closer inspection i think the reeds may be toast too.
what do you think.
Worn out reeds by mark.dobson, on Flickr
as always thanks in advance.
Mark
she might be older but still a fun ride.
- SS109
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Re: rebuild compression issue
Reeds are toast.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
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Re: rebuild compression issue
BURNT toast
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- bufftester
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Re: rebuild compression issue
Likely the source of your compression issue.
- KDXGarage
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Re: rebuild compression issue
define nearly :-) :-)
"i have had the reeds out and look ok and seem to lie nearly flat all over.
now retested and still only around the 80 mark.
am i missing some thing obvious ."
"i have had the reeds out and look ok and seem to lie nearly flat all over.
now retested and still only around the 80 mark.
am i missing some thing obvious ."
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- Two_stroke_brit
- Supporting Member I
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Re: rebuild compression issue
Thanks to all ,
i have a set on order.
cheers mark
i have a set on order.
cheers mark
she might be older but still a fun ride.
- Two_stroke_brit
- Supporting Member I
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- Location: Hockley TX
Re: rebuild compression issue
well new reeds are installed
but still cant get it to hold six pounds for a minute let alone 6.
again with the soapy water.
found a leak through the gear side of the kipps valve.
bollox.
must of damaged the seal on assembly.
top of again.
mark
but still cant get it to hold six pounds for a minute let alone 6.
again with the soapy water.
found a leak through the gear side of the kipps valve.
bollox.
must of damaged the seal on assembly.
top of again.
mark
she might be older but still a fun ride.
- KDXGarage
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Re: rebuild compression issue
That is a cheap and esy one to worry about compared to pulling it all apart again. You are almost there!
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