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Old 06-21-2008, 08:43 AM   #91
Lornce OP
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Quote:
Originally Posted by Stagehand
I was looking forward to seeing actual mechanics being done here, although you tell a fine yarn Pics are great.
I hadn't been aware that you farmed the work out. I'll have to dig up your thread and review it.

What part of the "mechanics" of the project were you hoping to gain more insight into? It's hard to know what to include and what to gloss over. And it's hard to take pics when you're hands are covered in oil and grunge.

Anyhow, the new cam's installed along with new big end bearings, cylinders and seals/gaskets throughout. Valve guides were still good so a clean up and light lapping was all that was required to the valves, and decarbonization of heads and piston crowns. I've tried to include handy home remedies to work around the requirement for "official factory tools" etc.

Happy to answer questions about anything I might have glossed over.

One concern I still have is the oil filter canister which is nearly 5mm deep. From everything I've read it's supposed to be closer to 3mm. Early on in it's life when the machine was quite new it's oil pump and big end bearings were replaced under warranty after concerns over low oil pressure. I've seen the old oil pump parts and there's nothing wrong with them.

I suspect the only reason it's lasted this long has been because of it's attention to maintenance and relatively tame existence for the first 200k kms. It was ridden quite gently by the original owner.

Since I've owned it it's never felt quite right at higher engine revs. I've never has an oil pressure guage on it, but the evidence in the oil filter cannister leads me to suspect it may bypass at higher revs.

Either way I'm going to need to shim the oil filter o-ring to suit.

fwiw,
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Old 06-21-2008, 08:51 AM   #92
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Looking forward to the rest of the build with great interest.
Darn good looking ally panniers.
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Old 06-21-2008, 09:00 AM   #93
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Quote:
Originally Posted by Lornce
One concern I still have is the oil filter canister which is nearly 5mm deep. From everything I've read it's supposed to be closer to 3mm. Early on in it's life when the machine was quite new it's oil pump and big end bearings were replaced under warranty after concerns over low oil pressure. I've seen the old oil pump parts and there's nothing wrong with them.
The canisters were set at varying depths by the factory added to the fact that if they were not sunk completely than they can move over time-- By judicious use of a caliper Anton has worked out a shim to control the canister insertion depth. When he was working on mine he installed a shim and then the can so that I no longer need a metal shim or a paper gasket. I now use 1 white o-ring and nothing else.

Here's a link to his stuff:


http://largiader.com/tech/filters/canister.html

I'll figure out some questions.
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Old 06-21-2008, 09:43 AM   #94
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Quote:
Originally Posted by Stagehand
The canisters were set at varying depths by the factory added to the fact that if they were not sunk completely than they can move over time-- By judicious use of a caliper Anton has worked out a shim to control the canister insertion depth. When he was working on mine he installed a shim and then the can so that I no longer need a metal shim or a paper gasket. I now use 1 white o-ring and nothing else.

Here's a link to his stuff:


http://largiader.com/tech/filters/canister.html

I'll figure out some questions.
This is freaking me out. I'm new to the airhead ('91 BumbleBee) An oil filter giving guff? I thought those krauts had it all figgerd out.

The Vert screwed with this post 06-21-2008 at 09:58 AM
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Old 06-21-2008, 09:45 AM   #95
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Quote:
Originally Posted by Stagehand
Here's a link to his stuff:

http://largiader.com/tech/filters/canister.html

I'll figure out some questions.
Thanks for the link, Stage.

That's some very useful information.

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Old 06-21-2008, 09:51 AM   #96
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Quote:
Originally Posted by Berni
This freaking me out. I'm new to the airhead ('91 BumbleBee) An oil filter giving guff? I thought those krauts had it all figgerd out.

Post '77 airhead oil filter esoterica is one of the greatest unsung gaffs of modern motorcycling.

No other motorcyle in history requires more effort and information to successfully change oil and filter.



But we love them so we take the time... and hope the planets align in our favour.

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Old 06-21-2008, 10:06 AM   #97
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Quote:
Originally Posted by Lornce
Post '77 airhead oil filter esoterica is one of the greatest unsung gaffs of modern motorcycling.

No other motorcyle in history requires more effort and information to successfully change oil and filter.



But we love them so we take the time... and hope the planets align in our favour.

Surprised some clever engineer/business type hasnt come along to save us all. I havent a clue (yet) of the inner workings but isnt there a carved billet aluminum solution to everything?
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Old 06-21-2008, 10:12 AM   #98
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Quote:
Originally Posted by Berni
Surprised some clever engineer/business type hasnt come along to save us all. I havent a clue (yet) of the inner workings but isnt there a carved billet aluminum solution to everything?

The Solution is not billet, just a thin sliver of the same stuff as the oil filter canister. Lathed off a spare, as a matter o fact.

Welcome to the wide wide world of airheads. I like the bumblebees
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Old 06-21-2008, 11:17 AM   #99
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Originally Posted by Stagehand
The Solution is not billet, just a thin sliver of the same stuff as the oil filter canister. Lathed off a spare, as a matter o fact.

Welcome to the wide wide world of airheads. I like the bumblebees
At the risk of mucking up this thread, thanks for the welcome, Stagehand. Ya, the Bees' a keeper.....
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Old 06-21-2008, 11:35 AM   #100
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Originally Posted by Berni
At the risk of mucking up this thread, thanks for the welcome, Stagehand. Ya, the Bees' a keeper.....
This thread's waaaay beyond "mucked up".



Welcome to "Old Skool", Berni.

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Old 06-23-2008, 05:58 AM   #101
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More pics!!! show us your lifters!
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Old 06-23-2008, 06:29 AM   #102
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More pics!!! show us your lifters!

Sorry 'Chew, I never thought to photograph the lifters. Nothing special about them; they were stock.

Though I did coat them liberally with oil before I put them back in the case.

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Old 06-23-2008, 06:36 AM   #103
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How did you achieve the 12:1 CR? Is it dual plugged? I'm curious about the specifics it took to make it run well. It was running the stock cam previously with the 1050 pistons, large valve heads and 40mm Bings? Any mods done to the advance and timing?
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Old 06-23-2008, 07:23 AM   #104
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Originally Posted by Wirespokes
How did you achieve the 12:1 CR? Is it dual plugged? I'm curious about the specifics it took to make it run well. It was running the stock cam previously with the 1050 pistons, large valve heads and 40mm Bings? Any mods done to the advance and timing?
12:1 (185psi measured cold) is achieved by using a pair of '77 RS heads modded to suit the 1050 Venolias. Specifically - the Venolia's flat periphery. Think squish band as it was meant to be. (BMW's famous "squish band" top ends of the '77 S's and RS's are over 0.100" deep. ie: nice idea but practically useless).

Heads are machined for dual plugs, but I don't use them. I've had problems in the past with reliability from Dyna and Accel coils, so am a little shy about running dual plugs. I'm convinced it would run better at the bottom end with dual plugs, but the squish band is so effective it runs fine with only single plugs. Pre-ignition is not an issue, though I do need to run cooler plugs over the stock set up.

Previously, with the stock cam, modded heads and 1050 Venolias it ran great with 40mm carbs modded slightly richer - increases in torque and power were dramatic. Made off-road and trail riding especially easy with it's huge gains in low end torque/power. It'll idle up walls. Also, fuel efficiency increased to a fairly consistent 55mpg (imperial) which is better than the best of 44mpg it achieved in stock form.

Ignition system is completely stock except for a Harley Davidson coil I fitted in a pinch to replace a failed Bosch piece. It's been there 40k kms now and works without any discernable issues. Though "in theory" it's not idealy suited to the system.

muter mutter mutter...
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Old 06-23-2008, 10:44 AM   #105
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If I hear you right, the only changes were the 1050 pistons/barrels and the heads were modified?

Were the heads shaved to achieve the 12:1? How were they modified? What specifically was done to create the squish band?

I've got a 77R100S that supposedly has a 1050 kit (so I was told by the PO, though there are no receipts to prove it) and it's been dual plugged. Supposedly it's got higher compression too. With mods to the advance I've managed to get it running pretty good with minor pinging under hard accelleration but it would be better to eliminate it altogether.

It seems that you have the answer!
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