Stiff Throttle

[Bumwah]

I have been riding my 1974 R90/6 recently and found the throttle a little stiff. I took apart my throttle control. I thought the cables needed lubrication. What I found was the gear drive to the cable pull is wearing out.

2 pot metal gears activate the pulling action. These two gears are very worn and I think that’s the extra resistance in the pull on the cables. Anyone found this or

am I the lucky one? Other than replacing the assembly are there any options? The gears connect to the only chain on the bike, and connect to the two throttle cables. 47 years and it’s kaput? So much for longevity…

[dirtrider]

5 hours ago, Bumwah said:

I have been riding my 1974 R90/6 recently and found the throttle a little stiff. I took apart my throttle control. I thought the cables needed lubrication. What I found was the gear drive to the cable pull is wearing out.

2 pot metal gears activate the pulling action. These two gears are very worn and I think that’s the extra resistance in the pull on the cables. Anyone found this or

am I the lucky one? Other than replacing the assembly are there any options? The gears connect to the only chain on the bike, and connect to the two throttle cables. 47 years and it’s kaput? So much for longevity…

Afternoon Bumwah

 

Difficult to tell what your problem is over the internet, if the grip/gear & chain/gear are badly worn then that would probably be the place that I (personally) started. It might eventually need new cables also but the obvious place to start is those worn gears.

 

Prices isn't too bad on the grip tube & gear/chain (at least as far as BMW parts go)

 

Just verify that the parts are correct for your pre 1975 R90/6 as there is some question of the below cam  properly fitting the pre 1975 R90/6.

 

 

[Michaelr11]

As DR has already pointed out, the replacement throttle parts are not expensive. I have a 74 R60/6 and an 84 R100, and I have replaced the cam and throttle tube on both bikes.  They both wore out and replacing the throttle parts made the throttle work smoothly with no excessive pull.

[Bumwah]

Thank You and Merry Christmas to all…

This is what I hoped this forum would do! 

[Bumwah]

OK... I have tried to locate the two parts necessary to repair my issue. One is available, the throttle grip tube. The other, Part # 32 72 1 233 535

the Cam Disk 33mm is becoming a challenge. I haven't found a dealer that has one. Germany doesn't have one. They are backordered but, BMW hasn't made any, yet.

and every dealer or parts house has said they are NOT obsolete, they just haven't manufactured them. WoW!

So... Here I sit Broken Hearted...

[Michaelr11]

8 minutes ago, Bumwah said:

The other, Part # 32 72 1 233 535, the Cam Disk 33mm is becoming a challenge. I haven't found a dealer that has one. Germany doesn't have one. They are backordered but, BMW hasn't made any, yet.

Try contacting Tom Cutter, Rubber Chicken Racing Garage.  He will often have parts for Airheads on hand that others have to order.

 

[Skywagon]

If Rubber Chicken can't help, then I would call Duane Ausherman.  He is a good airhead source.  Here is his website.   Duane Ausherman BMW motorcycles – What I can remember after decades of working with BMW motorcycles (w6rec.com)

 

 

BMW parts sources – Duane Ausherman BMW motorcycles (w6rec.com)

 

 

 

[dirtrider]

16 hours ago, Bumwah said:

OK... I have tried to locate the two parts necessary to repair my issue. One is available, the throttle grip tube. The other, Part # 32 72 1 233 535

the Cam Disk 33mm is becoming a challenge. I haven't found a dealer that has one. Germany doesn't have one. They are backordered but, BMW hasn't made any, yet.

and every dealer or parts house has said they are NOT obsolete, they just haven't manufactured them. WoW!

So... Here I sit Broken Hearted...

Afternoon Bumwah

 

Have you tried E-Bay?     (click on long link below)

 

      https://www.ebay.com/itm/292105523401?_trkparms=ispr%3D1&hash=item4402d890c9:g:cSAAAOSww9xZCk-t&amdata=enc%3AAQAGAAACoPYe5NmHp%2B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsS%2Fwocn770hnih0B3mVHNZ5B%2FY4P5tSjBk%2F7sujftsk5DkcPtZPcIgw7xjAekh%2F5bjDU9kKT1xLPjpisJIaOwZ4s9ACYPk2t9ktnObPQZ1or2Voy12uCcs%2FGthc6XM8jLii4LQIigGWIvqF2RNLOgnFOozndhLl0q3EHPmv7Hj6kFgjmilJwuq%2FjgwDKDgSGZh9cORwMHIm%2B019RmdDo4Tf0UB8oVbQ0U5QhusP2bW1N5QocwfW%2BHbj01kCIe%2Bo8HVO0hs4MqHGA9DJnwhVQDj3GI2MYT2IAEk3jmz86wtht7tYY0o8qTg1acgUR0DKNN%2BvZVuuXAJdPrGD8UXNFWNsQmxzZh4v2NTlR8zob8VkGyb9wLTpUH9bHc8J9MW3HYcCwkb%2F7Dt6Pdu2eLWtsDecmndUX%2Barm11miPkbyVMwZhBCxvV5dBUaueq%2FHp6YMNoJF3Mh%2FOh%2BzXS7aFmvkiMjn5ah%2FreNHRCglQ6Y1zdSvlq6TQf%2Bx4EU0nxNJw3ChAn9511d6i2Hn4z34S7voGBq4QNg%2FFsqRyfirbT%2FEruJnSwSoJUq6aDZF5nO3Xu1qgjuQG0Wp88WFSXcYcpLLYgdrw4Zyi0XEnxhHTYyXJqORXVV1tZvJmHpMZhpWZ%2BUPYAEyoti%2BqAr%2BbuKY0RKwMSXwFrzafIrJlsPg7pjh2qWTlaeamqPLExjyvFFDxP%2FpLh52nejLTes84%2FZzY44X73VmPiVlCVwgbv6z8IiEB%2BcQEn%2FJBDbGmtvMyALSZlcS8MHbz1XrbLMefk39VRSxynGDA0VqJSveliuGGPosytQOYJx763FY%2FuyGNh%2B761vz8%2BzsUlEXELjdsffkaSH0im%2Bg%3D%3D|clp%3A2334524|tkp%3ABFBM5O_cwOtf

 

 

 

[taylor1]

Go to bmwhucky  he's got one

[Bumwah]

Yo Yo Yo…

Dirt Rider, you have done it again! I make a simple request and YOU respond with a simpler answer!

After emailing everyone and their brother, I purchased the missing part via eBay. This should make riding my R90/6

easier and more enjoyable. It’s been a dream for 48 years. Thanks again!

 

Art

[Bumwah]

Bad News... Both parts are close butt, no cigar.

Both parts arrived yesterday and this morning I started to replace the original parts.

First the Cam Disk: NOT round as in 1974, has 2 lumps or lobes that interfere with the housing and the chain is 1/2 link longer.

Second the Throttle Tube: The locating groove that locks the tube in place with the top of the cover is 1/8 of an inch too far away to locate and slide.

Son Of A Bitch! I've never been this close and yet, so far away... Sometimes Heroes have feet of clay. I do have an unlimited supply of Duct Tape...

[dirtrider]

32 minutes ago, Bumwah said:

Bad News... Both parts are close butt, no cigar.

Both parts arrived yesterday and this morning I started to replace the original parts.

First the Cam Disk: NOT round as in 1974, has 2 lumps or lobes that interfere with the housing and the chain is 1/2 link longer.

Second the Throttle Tube: The locating groove that locks the tube in place with the top of the cover is 1/8 of an inch too far away to locate and slide.

Son Of A Bitch! I've never been this close and yet, so far away... Sometimes Heroes have feet of clay. I do have an unlimited supply of Duct Tape...

Evening Bumwah

 

That's too bad it didn't work out  (there was a question on it working on pre 1975 bikes) 

 

You might first go to this page to look around,  then go to the application chart link to understand what they have available. Then give them a call & explain your fitment problems, hopefully they can help you figure it out. 

 

I have bought other BMW parts from Euromotoelectrics & for the most part have been happy. 

 

 https://www.euromotoelectrics.com/product-p/hbgripcam463.htm

[Bumwah]

Thanx DR... I will check them out. I did take a file and some  emery cloth to the ring and pinion and lubricated the parts.

Then cleaned thoroughly, the lubricated and re assembled. Its back together and feels a little better, smoother, even a little easier.

San Jose BMW is checking out the throttle tube and I'll try to get in touch with the guy on eBay for the Cam Disk. Gee Whiz, the bike is only 48 years old!

They should have the parts in stock...

[Bumwah]

Today all is well in the kingdom! The correct cam disk arrived a couple of days ago. The throttle tube exchange was done today, courtesy of San Jose BMW. 

It all came down to, My 1974  components are from, the 1969-1974 era. My R90/6 is a first year model. The 1975 started the next series. Everything bigger and better.

Thanks again. It all fits like a glove and smooth, effortless throttle, Hell yea! Airheads Rule!

[Rinkydink]

So, your airhead is not really 100% shaft drive??

[Bumwah]

It turns out that my 1974 R90 has a chain. Shocking! . I knew it was there. I lubricated it once about 30 years ago. Anyway it went back together smoothly.
I did want to thank The two obscure parts locators. Capital Cycle in Sterling Va. and DR’s Ace in the Hole, Euro MotoElectrics in Denver, Co.

Rode today, Cruisin’ down Cańada Rd. And for a while, it was 1974..

Thanks to ALL!

[louisvillebob]

Also, there are aftermarket weaker throttle springs available to replace stock springs at the carburetors.  I forget who supplies.  I used these for years.