I pulled the heads this weekend and found that there were 2 of the thin base gaskets on each side. It appeared there was no sealant used, but they were not leaking. I cleaned them up and re-used them after applying a very thin layer of permatex gray since they actually looked better quality than the new gaskets I ordered!. Reassembled and all is well. Took her out for a couple rides Sunday, and yesterday. No oil leaking! Engine still clean and she is running well!
my dude had this nifty little tool that looked like a pipe with a partial gusset removed. Gave it a few taps with a hammer on the seal and boom... no leak... at all.
Thanks for throwing all these up onto the internet. I learn by watching and hearing rather than reading. With any luck, I'll be out ripping around on the '75 R90/6 I just got.
My old R60/6 did this procedure same way except used a ring compressor for a volkswagon engine made to work within the stud when sliding piston into jug. Difference is we oiled the rings and cylinder walls first. Later saw a Video where the tech just pulled the jug out enough to expose the cir- clip leaving the piston in the jug. If I get around to doing my R 80/7 think I will try the piston left in jug method. Don't really like disturbing the rings. The R 60/6 had paper case to jug gaskets. They came in several different thickness, while the newer motors went to the 'O' ring. I used a gasket thicker than one from factory to drop compression so could use regular gas...worked well. Nice video. Also local techs suggested using Yama seal on case behind rubber seals just a thin line near outer edge of case dish out. Once pass frame re- orient seals to correct position then push home. Also honda drive lube for Honda gold wings is far superior in molybdenum content then BMW's factory lube. Just passing on some good advice when the reader needs to service drive coupler when removing rear wheel
Great, didnt know to check this at all! We will always, from now on....by looking at each video, my doubts rockets ...that any workshop knows and deals with all this details at all...this is perfect care insight and good practise taken to a level of pure excellence...makes me happy Chris, and i understand your feelings when u encounter negligance...especially from workshops, who claim themselve workshop, but somehow miss the heart and soul, and perform half of the work, dont have a clue, and hand over these great engineering wonders, back in worse condition than you left them behind...i heard storys of cars that were mistreated by the workshops owners dog, leaving screwdrivers behind and blowing up motors...when i lately asked a dealer if he had checked the splines of a k100 he sold, amungst all other models and brands....he didnt have a clue what i was talking about...that makes me feel sad...and dissapointed...makes me swear as well😂😅lets face it, a lot of k100 owners dont even know the splines have to be checked and lubed...there is a lot of neglect followed by negligance and lazyness...admitting that i had no clue, before internet existed, what was needed maintaining my first motorcycles and cars, i was one of them, now im understanding motors and parts and sequenses of actions at high(er) level and it is addicting to learn more and understand more....it all makes sense Chris, you are the best my friend, Belgium🇧🇪 €urop here, regards Bob, hope u r fine Sir Chris!
Fabulous Chris, a video is worth a thousand words sometimes...and your use of expletives is so good too, nothing gratuitous and employed the right context. Had me in awe both for the learning and for the humour. I might even take those little weeping bastards on! - 1992 R80RT
You guys are building an amazing library of information about these machines. This is just the kind of stuff I was looking for when I started rebuilding my R100/7 some 3 years ago. THANK you for sharing all this great information.
I saw this elsewhere as well. It's the "that will de-compress other 1976-on airheads, but is generally not needed in the USA." part that gets me. So apparently My early 78 does not need the seal, but does have it currently.
Hey Chris, Just did the push rod overhaul at my R100RS '77 (no big O-ring). It was leaking really f**king bad, as you would say. It was indeed a push rod issue. Swapped the carter seal as well though, while I was at it. Made a aluminum strip tool for piston rings which I got replaced after some f**king about. Thanks for your great and clear videos! Really helpful! I'm now considering to install electronic ignition since I've got a misfire sometimes. I swapped the air filter now and it seems to be gone and runs smooth like a babies ass. If the misfiring returns I'll swap the ignition. Thanks again. Simon
Many thanks for an excellent video from a professional. I am going to have a shot at doing these seals on my 1978 R80/7 this winter and this has given me a lot of tips in visual form also.
Thanks again Chris. In the middle of cleaning all the Grime of the block around the PRT seals and such. Gonna pull the heads Friday or Saturday. Will Let you know how it all goes.
The later models (1980+ used o-rings at the cylinder base. Earlier models had a metal cylinder base gasket that should have 3-bond added. Thanks, Chris
From the MAX BMW site: Recommended when doing a top end reseal. 1979 to 1995 Airheads. BMW added an extra o-ring groove in the cylinder foot in May of 1979. If your (cast iron) cylinder does not have a groove for the big 11111337567 o-ring, then this o-ring does not apply. These only apply to Nikasil cylinders. Exception: there is a low octane metal base gasket specified for the 1976 R60/6 and 1977 R60/7 that will de-compress other 1976-on airheads, but is generally not needed in the USA.
Right. Assemble it without a base gasket and gently turn the engine over with a ratchet at the front of the crankshaft with the spark plugs out. If there is any binding you are likely making the piston contact a valve. Disassemble and install the thin base gasket and try again or add an additional head gasket perhaps. I have not run into this problem before.
Thanks too. I've got an '80 R100 series. At least one previous owner has done some mods. But in any event no one has seriously farked anything up. Someone posted your stuff on reddit
Great video! I've got a 84 R100 with leaking pushrod tube seals. Thank you. You crack me up too! I've got a set of seals, new but they have been around a while. Should I buy new ones?
My understanding is that if it has the gasket I should continue using one to prevent the piston rings from colliding with a potential carbon deposit ring at the top of the piston stroke. I also read that there were 3 different gaskets at various thicknesses available with one being most common. So I need to figure out which I have to continue.
Perhaps next year I'll have a "proper" top end rebuild done. Valves, guides rings etc. But I'll ride her this year as I always have with gentle adoration, and the occasional "spirited" moments. I do love this machine. Thanks for all the tips, and suggestions, and of course the videos, both informative and entertaining! Perhaps I'll make it out sometime to the shop Chris ( I live in Rollinsford NH) and bring you a beer. You drink beer? if so what's your brew of choice? Be well, Happy Spring!
Hey Chris, First thanks for the videos. They along with a couple of articles I read have given me the boost in confidence to do this project. There is a snag though. It is obvious to me that my 78 R100/7 has cylinder BASE gaskets (shims) present! No where in fiche, articles or your videos do I see any mention of these. Also I noticed you don't use any sealant at cylinder base (drei bond 1209) your thoughts? Thanks -Chris
Many had these goofy low-compression / compression reduction thick base gaskets added. After all, remember how horrible fuel was in the 1970's? I don't either! ;) So, what to do? Go with as thin as possible or none at all if possible. You still won't be above 10.5:1 ratio so you can still run on normal pump gas.
The bike has always run great, and all I really want is to replace the PRT seal since they are a MESS! Could I simply reuse the metal base gasket? I have found little info on the subject
Chris, if you replace the push rod tubes what setting do you use for the collars, am trying to find the correct setting for this for my R80/7'am using S/S replacements. Phil J in NZ
I've watched many of your videos and sometimes hear this clicking sound coming from off camera. I'm just curious what it is. You can hear it many places in this video but one I noted was at 7:55.
There is no need to replace it. However, please measure it. There was a thin base gasket and a thick one to lower compression to compensate for low quality fuel whatever the hell that was on the 1970's - 1980's!! If you have the thick gasket throw it away as it lowered compression by over one point from 8.5 to 7.3 as I recall. The thick gasket is really thick unlike the paper-thin aluminium original base gasket.
+Phill B • Maybe so you can do the other cylinder. The view window is only on the left side of the engine. I'm no expert, but I think that is what he is explaining starting at 10:10 .
the ot mark points the top dead center, at wich point the valves are closed and there is no tension on the rockers or pushrod so you can dismount and mount them hasselfree
Авто/Мото
I pulled the heads this weekend and found that there were 2 of the thin base gaskets on each side. It appeared there was no sealant used, but they were not leaking. I cleaned them up and re-used them after applying a very thin layer of permatex gray since they actually looked better quality than the new gaskets I ordered!. Reassembled and all is well. Took her out for a couple rides Sunday, and yesterday. No oil leaking! Engine still clean and she is running well!
my dude had this nifty little tool that looked like a pipe with a partial gusset removed. Gave it a few taps with a hammer on the seal and boom... no leak... at all.
I don't even have a boxer twin but this was so much fun to watch. Great tips and explanation...
Thanks for throwing all these up onto the internet. I learn by watching and hearing rather than reading. With any luck, I'll be out ripping around on the '75 R90/6 I just got.
My old R60/6 did this procedure same way except used a ring compressor for a volkswagon engine made to work within the stud when sliding piston into jug.
Difference is we oiled the rings and cylinder walls first.
Later saw a Video where the tech just pulled the jug out enough to expose the cir- clip leaving the piston in the jug. If I get around to doing my R 80/7 think I will try the piston left in jug method. Don't really like disturbing the rings. The R 60/6 had paper case to jug gaskets. They came in several different thickness, while the newer motors went to the 'O' ring. I used a gasket thicker than one from factory to drop compression so could use regular gas...worked well.
Nice video. Also local techs suggested using Yama seal on case behind rubber seals just a thin line near outer edge of case dish out. Once pass frame re- orient seals to correct position then push home. Also honda drive lube for Honda gold wings is far superior in molybdenum content then BMW's factory lube. Just passing on some good advice when the reader needs to service drive coupler when removing rear wheel
Your really the best damn bmw airhead mechanic on Utube !
Great, didnt know to check this at all! We will always, from now on....by looking at each video, my doubts rockets ...that any workshop knows and deals with all this details at all...this is perfect care insight and good practise taken to a level of pure excellence...makes me happy Chris, and i understand your feelings when u encounter negligance...especially from workshops, who claim themselve workshop, but somehow miss the heart and soul, and perform half of the work, dont have a clue, and hand over these great engineering wonders, back in worse condition than you left them behind...i heard storys of cars that were mistreated by the workshops owners dog, leaving screwdrivers behind and blowing up motors...when i lately asked a dealer if he had checked the splines of a k100 he sold, amungst all other models and brands....he didnt have a clue what i was talking about...that makes me feel sad...and dissapointed...makes me swear as well😂😅lets face it, a lot of k100 owners dont even know the splines have to be checked and lubed...there is a lot of neglect followed by negligance and lazyness...admitting that i had no clue, before internet existed, what was needed maintaining my first motorcycles and cars, i was one of them, now im understanding motors and parts and sequenses of actions at high(er) level and it is addicting to learn more and understand more....it all makes sense Chris, you are the best my friend, Belgium🇧🇪 €urop here, regards Bob, hope u r fine Sir Chris!
Love your videos Chris. Way to empower the Airhead owner.
I also love the fact that I can hear Echo And The Bunnymen in the background :)
Fabulous Chris, a video is worth a thousand words sometimes...and your use of expletives is so good too, nothing gratuitous and employed the right context. Had me in awe both for the learning and for the humour.
I might even take those little weeping bastards on! - 1992 R80RT
You guys are building an amazing library of information about these machines. This is just the kind of stuff I was looking for when I started rebuilding my R100/7 some 3 years ago. THANK you for sharing all this great information.
I saw this elsewhere as well. It's the "that will de-compress other 1976-on airheads, but is generally not needed in the USA." part that gets me. So apparently My early 78 does not need the seal, but does have it currently.
Chris, thanks again for this complete and instructive set of videos, you rock!
Thank you very much for the videos and paying it forward.
Now I have the confidence to tackle this on my 1984 R80 RT.
Excellent tutorials! I use them frequently. Thanks!
Hey Chris,
Just did the push rod overhaul at my R100RS '77 (no big O-ring). It was leaking really f**king bad, as you would say.
It was indeed a push rod issue. Swapped the carter seal as well though, while I was at it. Made a aluminum strip tool for piston rings which I got replaced after some f**king about. Thanks for your great and clear videos! Really helpful!
I'm now considering to install electronic ignition since I've got a misfire sometimes.
I swapped the air filter now and it seems to be gone and runs smooth like a babies ass.
If the misfiring returns I'll swap the ignition.
Thanks again.
Simon
Massive thanks for these video treasures.
got me a 96 R100R classic, these tutorials are so much help to get into the mechanics of these beaties :)
Great vids man! Thanks for filming and posting your airhead work. I watch even if I don't have a maintenance issue. R75/7 here.
Many thanks for an excellent video from a professional. I am going to have a shot at doing these seals on my 1978 R80/7 this winter and this has given me a lot of tips in visual form also.
Good Luck.
Thanks again Chris. In the middle of cleaning all the Grime of the block around the PRT seals and such. Gonna pull the heads Friday or Saturday. Will Let you know how it all goes.
soon time for this procedure on my old gs, this has been very helpful, thanks!
Hey thanks Dan! EUBW has some good stuff and reasonably priced. Thanks for the heads up!
Great video 👍
The later models (1980+ used o-rings at the cylinder base. Earlier models had a metal cylinder base gasket that should have 3-bond added. Thanks, Chris
You're a lifesaver thank you very much
Thanks for your comments. Happy Holidays, Chris
Thank you very much for these Chris - from Brisbane Australia
You're welcome.
From the MAX BMW site: Recommended when doing a top end reseal. 1979 to 1995 Airheads. BMW added an extra o-ring groove in the cylinder foot in May of 1979. If your (cast iron) cylinder does not have a groove for the big 11111337567 o-ring, then this o-ring does not apply. These only apply to Nikasil cylinders.
Exception: there is a low octane metal base gasket specified for the 1976 R60/6 and 1977 R60/7 that will de-compress other 1976-on airheads, but is generally not needed in the USA.
Right. Assemble it without a base gasket and gently turn the engine over with a ratchet at the front of the crankshaft with the spark plugs out. If there is any binding you are likely making the piston contact a valve. Disassemble and install the thin base gasket and try again or add an additional head gasket perhaps. I have not run into this problem before.
Great job
Thanks too. I've got an '80 R100 series. At least one previous owner has done some mods. But in any event no one has seriously farked anything up.
Someone posted your stuff on reddit
Great videos, Awesome work Chris!! Could you make a video when possible of Push rod Tube Seal replacement in pre 1970 twin and single?
AWESOME! Thanks for the update :)
Thanks!
Thanks Chris. Now to find the base gasket. I don't see it in any of the online fiche's.
Great video! I've got a 84 R100 with leaking pushrod tube seals. Thank you. You crack me up too! I've got a set of seals, new but they have been around a while. Should I buy new ones?
Adjust the rocker arm endplay to 0.05mm
My understanding is that if it has the gasket I should continue using one to prevent the piston rings from colliding with a potential carbon deposit ring at the top of the piston stroke. I also read that there were 3 different gaskets at various thicknesses available with one being most common. So I need to figure out which I have to continue.
great video and helpful .....thx
You're welcome, Rastislav!
Many little tips as usual. Thanks
You refer repeatedly to the bike as an R100RT. It probably WAS one?
Perhaps next year I'll have a "proper" top end rebuild done. Valves, guides rings etc. But I'll ride her this year as I always have with gentle adoration, and the occasional "spirited" moments. I do love this machine. Thanks for all the tips, and suggestions, and of course the videos, both informative and entertaining! Perhaps I'll make it out sometime to the shop Chris ( I live in Rollinsford NH) and bring you a beer. You drink beer? if so what's your brew of choice? Be well, Happy Spring!
Hey Chris, First thanks for the videos. They along with a couple of articles I read have given me the boost in confidence to do this project. There is a snag though. It is obvious to me that my 78 R100/7 has cylinder BASE gaskets (shims) present! No where in fiche, articles or your videos do I see any mention of these. Also I noticed you don't use any sealant at cylinder base (drei bond 1209)
your thoughts?
Thanks
-Chris
how many hours do you bill for this job? Great videos BTW. Thank you for making them.
Many had these goofy low-compression / compression reduction thick base gaskets added. After all, remember how horrible fuel was in the 1970's? I don't either! ;) So, what to do? Go with as thin as possible or none at all if possible. You still won't be above 10.5:1 ratio so you can still run on normal pump gas.
You should hone the cylinders regardless of what base gasket (OR NO GASKET) you choose.
The bike has always run great, and all I really want is to replace the PRT seal since they are a MESS! Could I simply reuse the metal base gasket? I have found little info on the subject
good set ty
You're welcome!
Chris, if you replace the push rod tubes what setting do you use for the collars, am trying to find the correct setting for this for my R80/7'am using S/S replacements.
Phil J in NZ
Hi Chris, For an r75/5 would I need to replace the original base gasket as well?
(The metal one)
Merci :-)!!!!!!!!!
What size clamps are you using Chris? I'm away from bike but would like to buy one for the job. Looking at 150mm examples on ebay. Thanks
I've watched many of your videos and sometimes hear this clicking sound coming from off camera. I'm just curious what it is. You can hear it many places in this video but one I noted was at 7:55.
Why not put an ajustment ring over the rocker axl, these are available with BMW
There is no need to replace it. However, please measure it. There was a thin base gasket and a thick one to lower compression to compensate for low quality fuel whatever the hell that was on the 1970's - 1980's!! If you have the thick gasket throw it away as it lowered compression by over one point from 8.5 to 7.3 as I recall. The thick gasket is really thick unlike the paper-thin aluminium original base gasket.
What is the importance of having the "OT bar on the fly wheel"?
+Phill B •
Maybe so you can do the other cylinder. The view window is only on the left side of the engine.
I'm no expert, but I think that is what he is explaining starting at 10:10 .
the ot mark points the top dead center, at wich point the valves are closed and there is no tension on the rockers or pushrod so you can dismount and mount them hasselfree
Thank you very much Dan! You can access my PayPal via my website AffordableBeemerServices What a kind gesture. Thank you very much :)
Jersey Cow Bavarian MONEY WERKS. Rocker arm assembly that much!!!!