Sideswipe's '81 CB900 Bol d'Or

started to pull the engine down!!

Here's how it's looking before any cleanup
 

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Good stuff! You got your work cut out for you now. Scrub-a-dub and then break out the measuring devices.
Pics like that just make me all giddy. :)
 
Not dead, I swear.

So I've gotten some time to get back into working on the bike, and since have purchased a parts washer!! woo!

The engine is completely striped down, gearbox looks fantastic condition however I have found one more problem beyond the carbs... one of the pistons looks like its in pretty bad nick (previously masked by about 10 mm of carbon build-up) and will need replacement.

Problem is I cant seem to find a replacement piston for a reasonable price (ebay wants $100 for it, when i can get OEM Spec big bore kits for $140 it seems like a hard ask)

Some of the covers have been cleaned up and sprayed satin black with photos forthcoming :)
 

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Have gotten off my rear end and got some more work done - painted up the covers and crank case so far. Going to get the cylinders bored next and then ill start reconditioning the heads before it's time to move onto the work on the frame :)

It's not the greatest job in the world, but it's not bad for a first attempt i think :)
 

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CB900F2C or F2B?

That's a lot of carbon in those combustion chambers. Can't tell if it's from running with clogged air filter or burning oil. If you can get a cost effective big bore kit. I'd get it bored out and honed to suit and start again with fresh bores. I tried running mine with pods and quickly realized that was a losing proposition and just bought an OEM airbox to fix it.

I always like the Roller Door though. Nice lines but hard to do much with. I finally painted mine somewhat like a CB1100R.
 
Teazer - Im not entirely sure tbh how do i check if its F2C or B?

Getting a big bore kit shortly so should run very nicely :) Also thinking of picking up some Khein carbs as well should be good :)
 
Sideswipe said:
Teazer - Im not entirely sure tbh how do i check if its F2C or B?

Looks like an F2B judging by the 5-spoke comstars. The Cs had the silver boomerangs. Good call with the big bore option too.

Look forward to seeing this come together.

cheers
ian
 
http://www.hoc.org.uk/gallery/bikes/801+.html

Ian,

You are correct. Silver banana comstars on the C and gold inside out comstars on the B.
 
Sideswipe said:
Not dead, I swear.

So I've gotten some time to get back into working on the bike, and since have purchased a parts washer!! woo!

What infectious enthusiasm.

That bike is worth serious coin as a restoration.
 
Not yet Rich!! but it is still in progress! There is some work being done on it and queued up at the moment:

There is some extra support being welded into the frame to prevent torsional twist, as per an interesting article i found here http://www.bikeme.tv/index.php/dons-cup-gold-ultimate-honda-cb900f/
probably not necessary, but i like the idea and it will not really effect the look the bike (except maybe look a bit nicer)

A mate of mine is a bike smash repairer that will be doing the paintjob. colour scheme is
high metallic blue frame
pealescent white fairings, tank etc.
matte black engine, wheels, and details (pegs, forks etc.)

so it's processing, slowly but surely :) Engine is being bolted back together, about to get bored out for bigger pistons!

In the meantime I have an XL250S (codename:project crapbag), post forthcoming, that I want to get on the road to get me to and from work. Its almost done too, just dealing with some electrical confusion :)
 
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