Newbie just bought 74 R75/6

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BMW74R75-6
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Joined: Sun Apr 25, 2021 10:47 am

Newbie just bought 74 R75/6

Post by BMW74R75-6 »

Hi All,

I ignored my better judgement and purchased this airhead. I don’t know squat. Who wants to go first? Thanks!

https://www.instagram.com/p/COF_ntwMvAX ... 965ka47pgm
Rob Frankham
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Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Newbie just bought 74 R75/6

Post by Rob Frankham »

Looks a nice clean bike. Probably refurbished not so long ago by the look of it. The fairing isn't original but that's not an issue, it looks like a R90s fairing or something similar.

What do you need to know.

Rob
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BMW74R75-6
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Joined: Sun Apr 25, 2021 10:47 am

Re: Newbie just bought 74 R75/6

Post by BMW74R75-6 »

Thanks, Rob. Apparently, it sat for some time. I don’t know how long though. The person I purchased from only had the bike for 2 weeks and didn’t know much. I rode it home about 60 miles. It seems there is some knock from the engine and the front brake is squeaky while moving but not necessarily when in use. Maybe it’s the forks. Since I know absolutely nothing, where should I start so that I don’t break it.
Rob Frankham
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Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: Newbie just bought 74 R75/6

Post by Rob Frankham »

My approach would be to replace all fluids ie. Engine Oil, Gearbox oil, driveshaft oil (in the right side of the swing arm),final drive oil, fork Oil, brake fluid & etc. Then carry out a full service checking valve clearances, ignition timing etc. I would dismantle the brakes and replace pads if necessary, replacing them with anti squeal paste. Check the rear brake. As far as the carbs are concerned, I would remove and clean the float bowls but I think I'd leave adjusting them, unless there were slow running problems, until I'd run the bike a few miles to see what running issues there are (or aren't). After that, it would depend what issues were found during the service and initial running.

If you haven't got a manual get one for oils, torques and other settings and last, but not least, don't listen to too many scare stories. Airheads are basically very sound and, as a general rule, require only regular maintenance...

Rob
Last edited by Rob Frankham on Tue Apr 27, 2021 4:47 am, edited 2 times in total.
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BMW74R75-6
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Joined: Sun Apr 25, 2021 10:47 am

Re: Newbie just bought 74 R75/6

Post by BMW74R75-6 »

Thanks for the info, Rob, much appreciated. I’ll start with the fluids and google/youtube.
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gspd
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Re: Newbie question

Post by gspd »

BMW74R75-6 wrote: Sun Apr 25, 2021 11:45 am Hi All,

I ignored my better judgement and purchased this airhead. I don’t know squat. Who wants to go first? Thanks!

https://www.instagram.com/p/COF_ntwMvAX ... 965ka47pgm
Have you checked for a bent frame?
If you stand on the foot pegs and look down at the engine, do your left and right cylinders line up perfectly? :o
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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Zombie Master
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Location: Vancouver Island BC Canada

Re: Newbie question

Post by Zombie Master »

gspd wrote: Mon May 03, 2021 1:09 pm
BMW74R75-6 wrote: Sun Apr 25, 2021 11:45 am Hi All,

I ignored my better judgement and purchased this airhead. I don’t know squat. Who wants to go first? Thanks!

https://www.instagram.com/p/COF_ntwMvAX ... 965ka47pgm
Have you checked for a bent frame?
If you stand on the foot pegs and look down at the engine, do your left and right cylinders line up perfectly? :o
:lol:
Any and all disclaimers may apply
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kmisterk
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Re: Newbie question

Post by kmisterk »

gspd wrote: Mon May 03, 2021 1:09 pm
BMW74R75-6 wrote: Sun Apr 25, 2021 11:45 am Hi All,

I ignored my better judgement and purchased this airhead. I don’t know squat. Who wants to go first? Thanks!

https://www.instagram.com/p/COF_ntwMvAX ... 965ka47pgm
Have you checked for a bent frame?
If you stand on the foot pegs and look down at the engine, do your left and right cylinders line up perfectly? :o
Okay now I'm curious. Should they?
Technology and Web enthusiast. I also like motorcycles.

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Zombie Master
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Location: Vancouver Island BC Canada

Re: Newbie question

Post by Zombie Master »

kmisterk wrote: Tue May 04, 2021 10:21 pm
gspd wrote: Mon May 03, 2021 1:09 pm
BMW74R75-6 wrote: Sun Apr 25, 2021 11:45 am Hi All,

I ignored my better judgement and purchased this airhead. I don’t know squat. Who wants to go first? Thanks!

https://www.instagram.com/p/COF_ntwMvAX ... 965ka47pgm
Have you checked for a bent frame?
If you stand on the foot pegs and look down at the engine, do your left and right cylinders line up perfectly? :o
Okay now I'm curious. Should they?
The cylinders have to be off set. GSPD is just being the "mechanic from hell." But do pay attention to what he says. He knows his shit. :)
Any and all disclaimers may apply
Rob
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Re: Newbie just bought 74 R75/6

Post by Rob »

Our connecting rods are side-by-side on the crank, so yes, offset is normal.

Some V-twins have a "knife & fork" con-rod big ends, which allow the cylinders to be inline.
Rob V
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