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I think I have a problem with one of the conrods - HELP

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Laverda Dave:
At least you caught it early Ted. If the engine had been fully built up and in the frame that would have been soul destroying.
As you say it has only cost a bit of Hondabond (and it goes off in the tube anyway so at least you are getting VFM!) and time. The bright side is you will know your way around the engine and it's all part of the learning process.
Good luck finding the problem and I'm enjoying the posts.

Bryanj:
Must admit to never finding an oval rod on a Honda motorcyle and not sure it could be recyified due to the tight tolerances Honda work to.
Also never seen a measurably oval pin but everything is older now so anything is possible.
Check back of shell and inside of rod eye is clean and dry

K2-K6:
Strange that something can be felt in rotation, and a bit puzzling.

The only "oddity" there is the oil supply hole but the shells should run clear of it for the oil to get round the centre groove. It's the only thing that could immediately be seen in the context of crank pin up or down in orientation I can think of. Wondering if there's anything snaggy on those shells for that rod.

Trigger:
Seen hundreds of oval Honda rods in my time. I measure up rods on a con rod reclaiming machine as, it has a dial on it.
Do you have all the rods on the correct way ?

It is always good practice to put the shells in the crank case, fit the crank without the rods, torque up and rotate by hand. And see if any shells are marked. Take the crank out and do the same with the rods on the crank. Checking while building is the best way to go  ;)

McCabe-Thiele (Ted):

--- Quote from: Trigger on June 03, 2021, 09:08:27 AM ---Seen hundreds of oval Honda rods in my time. I measure up rods on a con rod reclaiming machine as, it has a dial on it.
Do you have all the rods on the correct way ?

It is always good practice to put the shells in the crank case, fit the crank without the rods, torque up and rotate by hand. And see if any shells are marked. Take the crank out and do the same with the rods on the crank. Checking while building is the best way to go  ;)

--- End quote ---

Hi Trigger - yes the rods are all in the rightway round - as well as my original markings & photos this tallied with the bearing shell notches facing the exhuast side of the engine. It might be a coincidence but when I purchased the shells from Ziggy he only had 7 half bearings - all in sealed Honda NOS packets. I bought one Green shell from DS they had a different batch number  that might be a factor.
I'm even thinking could a dog hair have got in on assembly.
When I split the crankcase later today I will look for any marks on No 2 big end for an idea as to what is wrong.

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