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Post Info TOPIC: Bottom end engine rebuild - part 1 - taking it all apart!


Super Guru

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Bottom end engine rebuild - part 1 - taking it all apart!
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With the current interest in big bore kits that require the crankcases to be stripped for boring to take oversize sleeves I thought this would be a good time to create a pictorial guide to include a full strip down and rebuild.

I am hopeful that the 350cc big bore kit will prove successful and, if it is, the engine I used for the photos will be rebuilt as a 350cc for my brother Trev. I have another engine ready to use for my own kit wink

So, the guide only takes you as far as two empty cases. That said, they still have their bearings fitted and they all seem quite good, all run smoothly, so I am loathe to knock them out at this stage as new bearings would add a lot to the cost of the rebuild and, to be honest, it is rare for a bearing in the TTR crankcases to go bad. That said, I am tempted to replace the main bearings although the TTR ones are big enough to use in a tractor engine so that is probably unnecessary...... Decisions, decisions disbelief

See here

As usual feedback appreciated!

Brian



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great write up & photos brian maybee some photos of the gearbox end float shims not to forget about checking them before putting the crankcases together just a thought pal john

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Great work Brian. Photo's so much better than the diagrams in the manual.
Just awaiting part 2 - putting my 350 test mule motor back together and I'm not sure I've got the gearbox right - only seem to have 2 gears + neutral at the moment but I've run out of patience for the day and will attack it again tomorrow and see whether I've got to crack it open again...
Appreciate the huge effort you go to on these how-to threads, thank you.
Simon.

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simon i have had this many times building up crankcases taken them apart nothing wrong only gears are too dry not enough oil fill with oil select gears when done drain oil may nelp

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Super Guru

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I better get on with getting my one ready!



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When I have a delivery date for pistons Steve I'll let you know, and the race is on!

Thanks for the vote of confidence John. Going out to have a play now...

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