So I looked through my Clymers book, the OEM manual, and did a quick search here and couldn't seem to find anything on it, but does anyone know the size/spec for the small end of the Con Rod and the wrist pin? The pin measures .6693", and I can't find my telescoping bore gauges to measure the rod but there seems to be a very small bit of play. Can anyone lend a calibrated opinion on this? Thanks, Chris.
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Con Rod Small End Dia and Pin Spec
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For some reason there isn't a size spec furnished for the small end of the rod; Clymer says to check it and refer to 'table 1', but no spec found there....
All the FSM says is to check the pin fit and 'there should be no noticable vertical play' (page 3-25)...
The way I would read that is if you find any play and the pin isn't measurably worn (where the pin contacts the rod vs the piston), then you need a new rod.Fast, Cheap, Reliable... Pick any two
'78E original owner - resto project
'78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
'82 XJ rebuild project
'80SG restified, red SOLD
'79F parts...
'81H more parts...
Other current bikes:
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'86 XL883/1200 Chopper
'82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
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Yep, can't leave nuthin' alone...
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The last little ends and pins I put back together had a small amount of play on the piston if you rocked it side to side in a clockwise and anticlockwise motion looking at the front of the engine (not sliding side to side which there'll be loads of play)
BUT holding the piston quite tightly I couldn't feel any play UP and DOWN..... Vertical play that Steve mentions
If that helps, I'd hate to see good rods being scrapped when they're perfectly servicable.
This engine is the quietest I have for mechanical noise. (Its also the engine with the copper head gasket, relevant? nope )Tom
1982 5K7 Sport, restored to original from a wreck
1978 2H9 (E), my original XS11, mostly original
1980 2H9 monoshocked (avatar pic)http://i145.photobucket.com/albums/r...psf30aa1c8.jpg
1982 XJ1100, waiting resto to original
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Try your test again with the parts fully oiled. There has to be enough clearance for oil to be present. When I rebuilt both my 78 and 79 engines there was the smallest amount of play at the rod small end to wrist pin. It was so small that it was almost undetectable and I was questioning myself about weather I was really feeling anything. When I added oil no play was detectable.
RobKEEP THE RUBBER SIDE DOWN
1978 XS1100E Modified
1978 XS500E
1979 XS1100F Restored
1980 XS1100 SG
1981 Suzuki GS1100
1983 Suzuki GS750S Katana
1983 Honda CB900 Custom
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Once I get a coffee into me, I'll go and check it out. The play I was feeling was the "clockwise/counterclockwise" that Tom was explaining about (couldn't figure out how to describe it at 1.00 am this morning). The actual up/down play was very hard to feel, almost undetectable, and everything is clean so I'll try it again with oil, didn't even click in that there should be a small bit for an oil film, thanks gents!
Chris.1981 LH - First bike, a work in progress.
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Dial indicator
deeLux, it won't tell you if there are any high spots or tapers throwing off the measurements but if you have a dial indicator and an adjustable stand you can measure the apparent play between the wrist pins, the pistons, and the connecting rods.
Fit the pins loose in the pistons, then check the play by prying gently with a wooden dowel and watch the dial indicator. Do the same with the pins and connecting rods.-- Scott
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2004 ST1300A: No name... yet
1982 XJ1100J: "Baby" SS Brakes, '850 FD, ACCT
1980 XS1100G: "Columbo" SS Brakes, '850 FD, ACCT
1979 XS1100SF: "Bush" W.I.P.
1979 XS1100F: parts
2018 Heritage Softail Classic 117 FLHCS SE: "Nanuk" It's DEAD, it's not just resting. It is an EX cycle.
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Hope this helps
These measurements were on a 79SF motor with about 30,000 miles. Taken by a machinist friend.
Connecting rod diameter (pin end) in inches
#1 #2 #3 #4
.6525” .65195” .65195” .6523”
Wrist pin diameter in inches
.6519” .6519” .6519” .6519”
As you can see the tolerances were .001" or less throughout.Mike Giroir
79 XS-1100 Special
Once you un-can a can of worms, the only way to re-can them is with a bigger can.
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