ADVrider

Go Back   ADVrider > Bikes > Old's Cool > Airheads
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 10-11-2012, 03:27 PM   #16
Jay.T
Adventurer
 
Joined: Nov 2009
Location: Wisconsin
Oddometer: 59
It does work on late model airheads. I had to first take up as much space as I could with the shims and then clamp the rest out. My rockers now sound smooth.

About a year ago someone told me to clamp them, but I though they were getting the different models years and adjusting techniques mixed up. After the clamping technique and late model airheads came up earlier this summer on this site, I tried it. I figured now I heard it twice. A couple thousand miles and they still sound smooth.
Jay.T is offline   Reply With Quote
Old 10-12-2012, 08:31 AM   #17
woodly1069
Beastly Adventurer
 
woodly1069's Avatar
 
Joined: Jun 2008
Location: Louisville, KY...really too far from the hills!
Oddometer: 1,616
Hate to stray off topic, I know the bike in question is much newer than my 1973 airhead but do they all have needle bearings under the rockers? My right head is much more noisy than the left and I have tried clamping with no success. Now wondering if I have needle bearings. Current microfiche don't show a part number...thanks!
woodly1069 is offline   Reply With Quote
Old 10-12-2012, 08:41 AM   #18
Airhead Wrangler
Adios Mexico
 
Airhead Wrangler's Avatar
 
Joined: Mar 2008
Location: Back in Seattle, FINALLY
Oddometer: 6,283
Quote:
Originally Posted by woodly1069 View Post
Hate to stray off topic, I know the bike in question is much newer than my 1973 airhead but do they all have needle bearings under the rockers? My right head is much more noisy than the left and I have tried clamping with no success. Now wondering if I have needle bearings. Current microfiche don't show a part number...thanks!
If they're original then no, you don't have needle bearings in those, just bronze bushings up through '73. They are upgradable to the /6 type with needle bearings if they are in fact hosed... and they often are.
__________________
R80ST Gets The HPN Treatment
Seattle to TDF on an airhead

Current rides: HPN #834, '93 R100GSPD "red rocket", '73 R75/5 Toaster mongrel, '80 Ducati Pantah 500SL, '92 DR350, '67 Honda SS50, '80 Honda Chaly.

Airhead Wrangler screwed with this post 10-12-2012 at 08:56 AM
Airhead Wrangler is offline   Reply With Quote
Old 10-12-2012, 08:44 AM   #19
some_guy OP
Gnarly Adventurer
 
some_guy's Avatar
 
Joined: Sep 2012
Location: NoVa
Oddometer: 144
Quote:
Originally Posted by woodly1069 View Post
Hate to stray off topic, I know the bike in question is much newer than my 1973 airhead but do they all have needle bearings under the rockers? My right head is much more noisy than the left and I have tried clamping with no success. Now wondering if I have needle bearings. Current microfiche don't show a part number...thanks!
http://bavarianmotorcycleworkshop.com/tech-articles/valve-adjustment-seminar-bmw-air-head-engines-1970-onward


Style #1 The very early /5 models had rocker arms that were pivoted on a bushing. This style of rocker arm was narrow vertically and had a spacer on the pivot shaft about the same height as the rocker itself. They were prone to early wear so most of them have been updated to one of the newer styles described below. If you still have a BMW with this style rocker it would be a good idea to remove the rocker arms one at a time and check for wear in the bushing and the pivot shaft. If wear is evident, it would be best to update the rocker arms to a more modern style.

Style #2
The later /5s and /6 models had full length rocker arms that filled the whole space between the RAPB’s. These were pivoted on caged needle bearings, two (or a pair) per rocker arm. On this and the above mentioned Style #1 rocker arm sets, the RAPB’s were not indexed to the head. The RAPB’s simply sat on a tube that the 10mm studs went through and had enough slop in them to adjust the position of the RAPB’s. This is where being a mechanic becomes very important! Not only does the vertical clearance need to be set (as described below) but the entire shaft + RAPB’s + rocker arm + pushrod assembly must be set exactly square on the head and positioned so that the pushrod does not hit the inside of the pushrod tube as the valve opens and closes.

Style #3
The /7 through 1984 models had full length rocker arms that were pivoted on a pair of caged needle bearings per rocker arm. These had RAPB’s that fit loosely over a bushing that was pressed into the head and went around the 10mm studs. On this style rocker, the vertical clearance still needs to be adjusted, but there is no need to be concerned about the pushrod hitting the inside of the pushrod tube.

Style #4
Found on 1985 and through end of production for air heads, this was the most advanced and best of the rocker arm systems. The rocker was pivoted on two caged needle bearings per shaft. They incorporated a plastic noise dampening bushing into the rocker arm. The RAPB’s were precisely indexed into the head and the vertical clearance is set with shims that are available in various thicknesses. Once this style of rocker was run in and properly set, it was very unusual to ever have to reset the vertical clearance; and, there was never a concern for the pushrod ever touching the inside of the pushrod tube.
some_guy is offline   Reply With Quote
Old 10-12-2012, 08:44 AM   #20
woodly1069
Beastly Adventurer
 
woodly1069's Avatar
 
Joined: Jun 2008
Location: Louisville, KY...really too far from the hills!
Oddometer: 1,616
Thanks to the both of you for the very informative info! My only question is, what is a RAPB's? Mine look like this:

Don't mind the missing intake valve spring there, it was replaced!

woodly1069 screwed with this post 10-12-2012 at 08:50 AM
woodly1069 is offline   Reply With Quote
Old 10-12-2012, 08:59 AM   #21
Airhead Wrangler
Adios Mexico
 
Airhead Wrangler's Avatar
 
Joined: Mar 2008
Location: Back in Seattle, FINALLY
Oddometer: 6,283
Quote:
Originally Posted by some_guy View Post
http://bavarianmotorcycleworkshop.com/tech-articles/valve-adjustment-seminar-bmw-air-head-engines-1970-onward

Style #2[/B] The later /5s and /6 models had full length rocker arms that filled the whole space between the RAPB’s. These were pivoted on caged needle bearings, two (or a pair) per rocker arm. On this and the above mentioned Style #1 rocker arm sets, the RAPB’s were not indexed to the head. The RAPB’s simply sat on a tube that the 10mm studs went through and had enough slop in them to adjust the position of the RAPB’s. This is where being a mechanic becomes very important! Not only does the vertical clearance need to be set (as described below) but the entire shaft + RAPB’s + rocker arm + pushrod assembly must be set exactly square on the head and positioned so that the pushrod does not hit the inside of the pushrod tube as the valve opens and closes.
[B]
As far as I know, that's not correct. No /5 models were shipped with the needle bearing rockers. The needle bearing rockers were introduced with the /6s. In fact some early /6s, only R60 and R75 models it seems, were still shipped with the bushed rockers and not the needle bearing ones as the factory had to consume its remaining stock of the bushed rockers. It seems the factory acknowledged their inferiority as during the transition between the two types they only installed the bushed rockers on R60/6 and R75/6 models and put nothing but the newer, better needle bearing rockers on their flagship R90/6 and R90S models.
__________________
R80ST Gets The HPN Treatment
Seattle to TDF on an airhead

Current rides: HPN #834, '93 R100GSPD "red rocket", '73 R75/5 Toaster mongrel, '80 Ducati Pantah 500SL, '92 DR350, '67 Honda SS50, '80 Honda Chaly.

Airhead Wrangler screwed with this post 10-12-2012 at 09:58 AM
Airhead Wrangler is offline   Reply With Quote
Old 10-12-2012, 10:02 AM   #22
woodly1069
Beastly Adventurer
 
woodly1069's Avatar
 
Joined: Jun 2008
Location: Louisville, KY...really too far from the hills!
Oddometer: 1,616
guess I need to take her apart anyway to see how things are wearing and I will post a photo then, Thanks again guys!
woodly1069 is offline   Reply With Quote
Old 10-12-2012, 12:47 PM   #23
supershaft
because I can
 
Joined: Sep 2010
Location: San Francisco Bay area
Oddometer: 8,029
Quote:
Originally Posted by Airhead Wrangler View Post
As far as I know, that's not correct. No /5 models were shipped with the needle bearing rockers. The needle bearing rockers were introduced with the /6s. In fact some early /6s, only R60 and R75 models it seems, were still shipped with the bushed rockers and not the needle bearing ones as the factory had to consume its remaining stock of the bushed rockers. It seems the factory acknowledged their inferiority as during the transition between the two types they only installed the bushed rockers on R60/6 and R75/6 models and put nothing but the newer, better needle bearing rockers on their flagship R90/6 and R90S models.
You save me a lot of typing AW. It seems the factory ackowledged their inferiority going way back to the R69S since they had needle bearings. Did the R68? I am pretty sure the R54 did? Prewar GP bikes?
supershaft is offline   Reply With Quote
Old 10-12-2012, 01:03 PM   #24
disston
ShadeTreeExpert
 
disston's Avatar
 
Joined: Mar 2011
Location: Silver Spring, Md
Oddometer: 8,001
I owned a 1974 R90/6 that had bushed rockers. They were not /5 bushed rockers. They were the full length type /6 rockers. This was a long time ago and I don't have the bike anymore. I suppose the rockers could of been changed out by somebody else. In fact the guy I bought the bike from had low morel values and was rather unscrupulous. We were friends at the time.

I replaced those rockers with a Capital Cycle kit. Wrecked the bike and sold it to another guy that used to be a friend. He then wrecked this bike again. Not sure what ever became of the bike but the night he wrecked it he called my girl friend and had her take him and the R90/6 home in the trunk of her Dodge Dart.

Sorry it's such a long story. I can just never get over this one.
__________________
.
Never memorize something you can look up.
---Albert Einstein

Pay your debt, piratejohn.http://www.advrider.com/forums/showthread.php?t=949341
disston is offline   Reply With Quote
Old 10-12-2012, 09:00 PM   #25
chollo9
Screwed the Pooch
 
chollo9's Avatar
 
Joined: Jul 2003
Location: Silk Hope, NC
Oddometer: 1,004
Quote:
Originally Posted by disston View Post
Not sure what ever became of the bike but the night he wrecked it he called my girl friend and had her take him and the R90/6 home in the trunk of her Dodge Dart.
At least she didn't let him ride in the car.
__________________
"It's not that I don't like people...I just find I am happier when they're not around"
chollo9 is offline   Reply With Quote
Old 11-15-2012, 10:34 AM   #26
Airhead Wrangler
Adios Mexico
 
Airhead Wrangler's Avatar
 
Joined: Mar 2008
Location: Back in Seattle, FINALLY
Oddometer: 6,283
Quote:
Originally Posted by bmweuro View Post
I noticed the price on the 0.35 is over 3.00 while the rest are 73 cents. Buy 73 cent ones now before BMW raises the price to $3.57. This will happen when they have to reorder them from BMW AG.
DAMN! I waited. Now they're all $2.59 except for the .50. What a difference a month can make.

11 11 33 1 337 718 SHIM - 0,30 X $2.59
11 11 33 1 337 719 SHIM - 0,25 X $2.59
11 11 33 1 337 720 SHIM - 0,20 X $2.59
11 11 33 1 337 721 SHIM - 0,35 X $2.59
11 11 33 1 338 190 SHIM - 0,50 X $0.73
__________________
R80ST Gets The HPN Treatment
Seattle to TDF on an airhead

Current rides: HPN #834, '93 R100GSPD "red rocket", '73 R75/5 Toaster mongrel, '80 Ducati Pantah 500SL, '92 DR350, '67 Honda SS50, '80 Honda Chaly.
Airhead Wrangler is offline   Reply With Quote
Old 11-15-2012, 11:36 AM   #27
supershaft
because I can
 
Joined: Sep 2010
Location: San Francisco Bay area
Oddometer: 8,029
Quote:
Originally Posted by disston View Post
I owned a 1974 R90/6 that had bushed rockers. They were not /5 bushed rockers. They were the full length type /6 rockers. This was a long time ago and I don't have the bike anymore. I suppose the rockers could of been changed out by somebody else. In fact the guy I bought the bike from had low morel values and was rather unscrupulous. We were friends at the time.

I replaced those rockers with a Capital Cycle kit. Wrecked the bike and sold it to another guy that used to be a friend. He then wrecked this bike again. Not sure what ever became of the bike but the night he wrecked it he called my girl friend and had her take him and the R90/6 home in the trunk of her Dodge Dart.

Sorry it's such a long story. I can just never get over this one.
Early /6's came like that. That article up above is all wrong on numerous fronts.
supershaft is offline   Reply With Quote
Old 11-15-2012, 11:59 AM   #28
disston
ShadeTreeExpert
 
disston's Avatar
 
Joined: Mar 2011
Location: Silver Spring, Md
Oddometer: 8,001
I may be the only one with this opinion but I think bushed rockers work just fine as long as the bushings are in good condition. They used bushed rockers on the 427 and 428 FE Ford engines. Many, many other engines used bushed rockers. But most will up grade to a roller rocker if they have the money and there are usually kits to do this if you have the money. I think the kit to fit FE blacks was not available till Shelby came out with it about ten years ago. Now he's dead but the parts he made for those engines are still available.

I don't know if you can rebush the /5 rockers. Any time the subject comes up everybody starts chanting /6, /6, /6 so I just don't know if those bushings are available. Never heard of anybody doing it. If I had a /5 I think I would look into it.
__________________
.
Never memorize something you can look up.
---Albert Einstein

Pay your debt, piratejohn.http://www.advrider.com/forums/showthread.php?t=949341
disston is offline   Reply With Quote
Old 11-15-2012, 12:17 PM   #29
supershaft
because I can
 
Joined: Sep 2010
Location: San Francisco Bay area
Oddometer: 8,029
You can re-bush them. The problem is that usually the bushings start spinning in the rockers and wear the rocker arms out so that option is no more. The spinning bushings also usually wear out the shafts. The bushed setup works. They just don't work as well for nearly as long as the needle bearing setup. Plus, when a needle bearing does give up at usually a much later point, they usually don't eat the rocker and shaft at the same time.
supershaft is offline   Reply With Quote
Old 11-15-2012, 01:00 PM   #30
disston
ShadeTreeExpert
 
disston's Avatar
 
Joined: Mar 2011
Location: Silver Spring, Md
Oddometer: 8,001
Oh.
__________________
.
Never memorize something you can look up.
---Albert Einstein

Pay your debt, piratejohn.http://www.advrider.com/forums/showthread.php?t=949341
disston is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 09:40 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014