Top End rebuild time


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RE5Guy
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Top End rebuild time

Post by RE5Guy »

Hello all,

some weeks ago I posted re a problem I was having getting my bike to run on all 6. I started off thinking it may have been a timing issue.

Well I can report back that it was not timing. The bike had been sitting for such a long time on its side stand that all the left hand inlet valves had closed up due to moisture.

So now that it is apart, I have found damage to the bores as well as the head so I need to do a re-bore, new pistons (2nd oversize) and rings, gudgeons, gudgeon circlips, one inlet valve, stem seals, gasket set and maybe some lifters. Bottom end seems fine.

OK question #1. The reason I say maybe lifters is that some appear to be water marked. That is the chrome has become a dark grey colour on the face of the "downside" of some lifters, that is the lowest point they were touching the head if that makes sense. You can feel no difference to the texture of the lifter, it just looks different. I haven't tried to polish the marks out. What are peoples thoughts? Ok to use or should I replace them?

Question #2. Some idiot (ok it was me) manually turned the engine over with the rocker cover off but with the tacho drive in place and broke the casing just like my book says it will. Can these re repaired or does someone supply just that casing without having to buy the whole set?

Question #3. Is there a preferred supplier of parts or is there a supplier that is most likely to be able to supply all the bits I need at something close to a reasonable price. I have priced some of the bits through Honda here in New Zealand and to say it is expensive is an understatement compared to some of the prices I see on the internet.

Thanks guys

Tony

daves79x
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Post by daves79x »

CBXMAN has reproductions of the cam cap you need. I can get 2nd oversize Honda pistons and rings here for a bit less than $600 a set of six. How does that compare with your Honda dealer?

I would just clean up the buckets and reuse them. Make sure the 'A's go in the 'A' holes and the 'B's go in the 'B' holes. I really don't think you need new wrist pins - just new clips. A good set of valve seals are about $60 here.

Dave

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alimey4u2
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Post by alimey4u2 »

To add to Daves excellent advice, research www.bikebandit.com to check out availabilty & price of parts....
ICOA # 656

EMS
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Post by EMS »

The tach drive cam cap was available from Honda after 1980. It still may be. You could never buy a whole set anyway as they were line bored and came only together with the complete head. I will start a repair job for those with stripped threads or broken thread towers. Details to follow soon.

RE5Guy
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Post by RE5Guy »

Hello all.

I have now got all the bits I need, so that was the easy bit I guess.

A question, further to Dave's comment what is the difference between A buckets and B buckets and how do I tell which is which?

cheers

Tony

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cbxtacy
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Post by cbxtacy »

one out of four people in this country is mentally unbalanced
think of your three closest friends, if they're okay then
YOU'RE THE ONE

RE5Guy
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Post by RE5Guy »

Thank you sir.

I assume that the same applies for a '79 model?

cheers

Tony

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