Crash Damage

Discuss all things 1970 & later Airheads right here.
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George Ryals
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Location: Stone Mountain, GA

Re: Crash Damage

Post by George Ryals »

I had a crash with similar damage to the left head. It turned out that the cylinder flexed rearward enough to cause the cylinder base to leak at the upper rear corner. So along with replacing the head, I had a machine shop turn .020" off the base then added a .5mm shim to keep correct the compression.
Smile it's contagious!
'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts
chasbmw
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Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: Crash Damage

Post by chasbmw »

Nourish wrote:Well Duane you were right!

http://i120.photobucket.com/albums/o187 ... 1404651508

Now then will these gears all fit into a smooth gearbox shell?

There were a number of changes in internal parts between the early/mid and later gearboxes, so difficult to know if all the parts will successfully transplant, some one like Jim Cray or Steve Scrimmeger should know?
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Re: Crash Damage

Post by Nourish »

Well following on I bought a R75/6 frame tax exempt after next year (Uk road fund ) and transfered all of the lugs and brackets from the mono frame.
Removing the damaged R/H head I found that the barrel skirt had cracked but also found that the bike had been down the road before as the L/H head was a 40mm one(should of been 32mm) and that barrel was cracked too!
I fitted another pair of barrels I had with new rings and a pair of Mono 32mm heads that I had skimmed, twin plugged and gas flowed for mid range by Jim Cray.
I repaired the gear box end cover by machining of the damaged diameter and soldered on another that I turned up (http://www.frost.co.uk/lumiweld-kits.html).
I also machined the output shaft to fit the omited circlip, turned the shaft around in the lathe to tidy up the output flange taper and found that the shaft was bent!
http://i120.photobucket.com/albums/o187 ... CF1874.jpg
http://i120.photobucket.com/albums/o187 ... CF1875.jpg
http://i120.photobucket.com/albums/o187 ... 1417342298
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Zombie Master
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Location: Vancouver Island BC Canada

Re: Crash Damage

Post by Zombie Master »

Glad to hear you survived in tact. There is always more stuff.
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Duane Ausherman
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Re: Crash Damage

Post by Duane Ausherman »

Your first post mentioned the rear wheel bent to the right. That is why I thought about the output shaft being broken or bent. I have seen several bent, but only remember one that was broken. A cursory exam wouldn't suggest it and so that is why I brought it up.

You really want a full appraisal before sinking resources into it.

One time my shop had 10 wrecks in it. We were running out of room because wrecks seem to live longer in the shop before leaving. I examined them and 8 had badly worn tires. Cause and effect, I don't know. Maybe bad riders also didn't take care of maintenance. Or worn tires caused the wrecks.
Ask the Indians what happens when you don't control immigration.
Nourish
Posts: 194
Joined: Tue Aug 10, 2010 5:15 am
Location: Bristol, UK

Re: Crash Damage

Post by Nourish »

Well it's finally back up together.
I bought an 1975 R75 frame that will be UK road tax exempt in January. I removed and replaced all of the frame brackets from the Mono frame so I now have a mono'd R75 frame with an easy center stand. As I wanted to us a /5 tank I shortened the Mono subframe - this entailed 'kicking' up the back to clear the mudguard which had it's mounting part moved up to mount to the subframe. Where the subframe attaches to the main frame I welded the nuts on and used countersunk bolts to locate the subframe and also a removeable brace to the subframe under the seat. A brace was also made to locate the gearbox upper bolts the the spine of the frame, this meant that I had to cut the starter motor cover in half and weld on mounting lugs to fasten it back together aroung the brace. I made up a new seat and had it covered in faux suede.
I've used K75S forks and yokes. The mudguards I made up the patterns and molds and had glass copies made - the front being a Ducati monster blade with a lip put around the edge and bolts up to a custom made fork brace, the rear guard has had its sides reduced and a lip put back on.
I replaced both cylinder barrels as they had cracked and had the heads twin plugged and gas flowed for more midrange.
The wheels are both 18" as was the Mono - the rear having a modified GS hub.
I made a new rear lamp to fit to a lucas style lense and fitted smaller aftermarket indicators. and moved the ignition switch to where the seat lock was.
I've only done some 300 miles so far on it but it pulls really well and the whole bike feels really taught - I'm dead chuffed with it!

Image[/img]

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jagarra
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Location: Reno, Nevada

Re: Crash Damage

Post by jagarra »

WOW!!!! looks great. You did a wonderful job on the conversion, I really like the look of it.

gg
1974 R90/6 built 9/73
1987 BMW K75S
1994 BMW R1100RS
1964 T100SR Triumph
1986 Honda XL600R
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SteveD
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Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: Crash Damage

Post by SteveD »

I'm with Jagarra. The bike looks great as a sort of /6 and has the more modern airhead traits too! That'd be a great bike to own.
If it was mine, I'd put a set of Hoske mufflers on it. Those mono pipes look to unbalance it to my eye. Regardless, I'd love something like that to enjoy. It's a blend of style and practicality that leaves the modern cafe style way behind imho.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
tsa
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Location: Surrey, UK

Re: Crash Damage

Post by tsa »

That looks _very_ nice. A very skillful combination of classic looks and modern handling ability.

Any particular problems with fitting the K forks?
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'73 R75/5, '78 R80/7, '83 R80RT
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Ross
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Re: Crash Damage

Post by Ross »

I love how this has turned out. Very well done.
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