seizure disaster. should have known better

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graham heise
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Re: seizure disaster. should have known better

#16 Post by graham heise » Thu May 24, 2018 4:44 am

hondaror wrote:That wear is excessive piston to bore clearance. The piston was rocking front to back.
Yer i believe your right. I pulled the other jug and it shows something similar although not as bad. I have read that Back in the hey day of' racing 2 strokes, buyers would ask to pull of a cylinder to gauge crank and bore condition before settling on a price of the' bike. Anyone have or know of a set of cylinders for sale? I saw one right cylinder on Canadian ebay. That could be a start.

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Last edited by graham heise on Thu May 24, 2018 6:41 am, edited 1 time in total.
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graham heise
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Re: seizure disaster. should have known better

#17 Post by graham heise » Thu May 24, 2018 5:04 am

The other cylinder, right side. Image

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JonW
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Re: seizure disaster. should have known better

#18 Post by JonW » Thu May 24, 2018 5:06 am

I asked my mate about cyls and he doesnt have any now, sorry.

Ask in the wanted section of this forum, you never know your luck.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
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graham heise
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Re: seizure disaster. should have known better

#19 Post by graham heise » Thu May 24, 2018 5:18 am

thanks for asking jon w. i'll post up in the wanted section. I think boring to 2.5 over could be as they say false economy. i'm open to advice from here.
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JonW
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Re: seizure disaster. should have known better

#20 Post by JonW » Thu May 24, 2018 5:36 am

you can have them sleeved is another way, but with mixed results Ive heard locally, less so in the UK where people seem to go that route.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

graham heise
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Location: gold coast Australia

Re: seizure disaster. should have known better

#21 Post by graham heise » Fri May 25, 2018 3:56 am

i have been offered a pair of cylinders from a good forum member, both cylinders standard bore. Only trouble is one of the cylinders (right cylinder?) has suffered damage. i asked to get a second opion to it's viable condition. To me it looks like it may be to damaged to bore out without at least going to max 2mm overbore. probable hard to really know without boring to find out. looks like left cylinder would be good. anyone have a right cylinder? if i'm going to spend the money (allot) i would like to start at least only +1mm to allow future rebuilds. opinions welcome.
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graham heise
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Re: seizure disaster. should have known better

#22 Post by graham heise » Fri May 25, 2018 4:00 am

PhotosImageImageImage

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2smoke
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Re: seizure disaster. should have known better

#23 Post by 2smoke » Fri May 25, 2018 10:19 am

I would stick with what you have till you find a set you are happy with.
Colin
79 RD400F Daytona Special
81 RD350LC
89 TDR250
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hondaror
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Re: seizure disaster. should have known better

#24 Post by hondaror » Sat May 26, 2018 2:31 am

Wow, that's a lot of damage. My machinist eye says it needs a lot of attention. Only a good deal if you get them for a bargoon of a price.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
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two-stroke-brit
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Re: seizure disaster. should have known better

#25 Post by two-stroke-brit » Sat May 26, 2018 4:58 pm

that last pic screams for a re sleeve.
must of ran for a while with the piston in bits to cause that much carnage.
350LC,Athena 392 big bore,stock porting,swiss cheese air box,stock reeds,spec11 pipes.(now TSA big bore pipes)
She might not be pretty but she will always be a fun ride


1982 YAMA RD350LC
98KDX 220R
1967 TRIUMPH TIGER
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graham heise
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Re: seizure disaster. should have known better

#26 Post by graham heise » Mon Jun 04, 2018 5:14 am

Found some cylinders in Australia. Standard bore. ImageImage

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graham heise
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Re: seizure disaster. should have known better

#27 Post by graham heise » Mon Jun 04, 2018 5:17 am

Ok i bought some accessories to. Image

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hondaror
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Re: seizure disaster. should have known better

#28 Post by hondaror » Sun Jun 10, 2018 4:22 am

Nice find.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

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Re: seizure disaster. should have known better

#29 Post by Hooligan » Thu Aug 09, 2018 2:32 am

Its nice to have a spare engine. I've got two complete motors for my LC. I just switched to motor #2 last winter. Motor #1 ran in the bike for 3? years. Now Motor #2 will run for a few years and then I'll switch them again. This way I always have a motor ready to go and no motor sits idle for years to get rusty inside. :D
Kicking myself that i didn't spray starter fluid around carb joint to check for leeks. there had also been a little bit of oil around outside of reed block that i haden't noticed. i went over this bike for hours before running it up the road.
I had a badly leaking reed gasket and spraying carb cleaner around the reed block had zero effect. The primary symptom was an elevated idle.

Now, as a result of that experience, I use grey motoseal on all surfaces of the reed block and spacers. No leaks since.

Thing is i didn't at the time recognise the bike had seized at the top of that hill. It's since travelled another 200k's and i thought it was running great.
A friend tore down his 2-stroke enduro bike to discover a big piece of nikasil plating had flaked off. Strange thing was he never noticed any drop in performance, even though the position of the flake should have resulted in a large loss of compression. Short of a serious seizure I think a 2-stroke engine can tolerate a fair amount of cylinder/ring damage or wear and still run fine.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

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