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chuck
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greenville, oh
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i have recently purchased a 1973 R 75/5 it was stored in a garage atleast 4yrs before i purchased it i changed oils, spark plugs, gas lines, ran sea foam through a tank of gas and am now using a octane booster. it runs decently at low speeds now took off like a moped for the first week. but i still cant get it above 65 mph, 55mph is where it tops out most the time. the tach and speedo have a lot of movement in them the speedo seams about 5 mph off. so my question is any ideas what i need to do to get some top end out of this bike

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1973 BMW 75/5

JD
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Washington, NC
Joined: 07/28/2011
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If it's been sitting for

If it's been sitting for awhile with gasoline in the carburetor, your main jets could be clogged.

Darryl.Richman
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Surf City, USA (Santa Cruz, CA)
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Torn diaphragms in the carbs.

Torn diaphragms in the carbs.

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chuck
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greenville, oh
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more info i forgot earlier

chuck wrote:

i have recently purchased a 1973 R 75/5 it was stored in a garage atleast 4yrs before i purchased it i changed oils, spark plugs, gas lines, ran sea foam through a tank of gas and am now using a octane booster. it runs decently at low speeds now took off like a moped for the first week. but i still cant get it above 65 mph, 55mph is where it tops out most the time. the tach and speedo have a lot of movement in them the speedo seams about 5 mph off. so my question is any ideas what i need to do to get some top end out of this bike

it bogs down is the best way i can think to decribe what it does when i open the throttle to go faster than 55 mph. seams to run up in rpms nicely when in neutral.

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schrader7032
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San Antonio, TX
Joined: 10/27/2006
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Plugged air filter is also a

Plugged air filter is also a possibility. Check for squirrel's nests in the wrong places!!

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

chuck
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greenville, oh
Joined: 09/08/2011
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other info part2

forgot to shut fuel valve last night puddles of gas on both sides of bike this morning. air filter i tried to remove following owners manual instructions used flash light to look in there i dont see how it can come out the way the manual says

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TrophyMoto
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upstate s.c.
Joined: 03/29/2009
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torn diaphragms

Darryl.Richman wrote:

Torn diaphragms in the carbs.

+1

chuck
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greenville, oh
Joined: 09/08/2011
Posts: 11
thanks

guess i get to rebuild some carbs or try and find someone in ohio willing to do it for me

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schrader7032
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San Antonio, TX
Joined: 10/27/2006
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Air filter: this is the clam

Air filter: this is the clam shell variety. The plastic air horn have to come off the left carb. You might have to loosen the clamps that hold the carb to the head and move both the carb and air horn at the same time. It's a trick by the German engineers! Remove the long screw from the left cover. Reach in with your fingers and begin to wiggle the left half of the clam shell and pull towards you. It might hang up on the engine badge that's on the engine. If it was glued on slightly to the rear, the filter cover will catch on it. DAMHIK!

Where in Ohio? Check this link for friendly Airhead shops:

http://micapeak.com/bmw/Airhead-Shops.html

I know of a guy in Wayne, OH, although he deals with more vintage bikes than yours.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

chuck
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greenville, oh
Joined: 09/08/2011
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ok

found one about 100 miles away which isnt bad of course he is swamped cant get to me for a couple weeks. i am about 40 miles north of dayton ohio real close to indiana border, didnt see guy in wayne ohio on that list

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schrader7032
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San Antonio, TX
Joined: 10/27/2006
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He wouldn't be on that list.

He wouldn't be on that list. But I can email him and see if he's interested in doing this work.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

chuck
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greenville, oh
Joined: 09/08/2011
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if

if mapquest gave correct location he is about 3to 400 miles away i think thats a litle far to go but thanks anyway

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chuck
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greenville, oh
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finding parts

if anyone can post a link to some decent part supplies i would apperciate it

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schrader7032
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San Antonio, TX
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Bob's BMW -
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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

wolds
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carb rebuild

Chuck, you might want to call Repsycle in Lithopolis OH. and talk to Rick Hanson their mechanic. They are located about 1/2hr S/E of Columbus and are a very good resource. They can be reached at 614-837-1160. Warren

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1976 BMW R90S
1976 BMW R60/6

drpboston
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Joined: 05/25/2011
Posts: 19
Diaphragms?

I have a small drip when mine sits, happens after cool down following running her for a few hours. Otherwise runs fine.

any good write-ups on this? Clymer manual en-route, but I'm sure it's been discussed ad-nauseum here. Smile

brixtonsaint
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New Castle, DE
Joined: 06/28/2011
Posts: 115
I had gas coming out of one

I had gas coming out of one of my carbs, at first everyone said to flush it and it should work. I flushed a little, nothing happened then tried 10 other things. Also wouldn't get much above 55. Put in-line fuel filters on and flushed a gallon through the carb. It actually worked and the leak is gone and the bike moves much better. Might be worth another try before you drop a lot of $$$.

chuck
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greenville, oh
Joined: 09/08/2011
Posts: 11
what exactly do you mean by flush

a gallon of gas through

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brixtonsaint
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New Castle, DE
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It seemed like that much, I

It seemed like that much, I figured I would give it enough time since the first attempts didn't work. Just put a funnel with 5 coffee filters in it and ran the gas back into my fuel can for the mower. I really didn't think it would work especially after trying it with just letting a little fuel run through a few times before. I'm learning to not question the results or reasoning, if they work then hop on and ride as much as possible until the next thing happens. Plus a gallon is under $4.00, it's worth a shot.

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