1975 BMW R75/6 Install Siebenrock 1000cc Upgrade Kit

[@charleshof6394]

Thanks for the very nice documentation on not just how, but also the why and reasoning behind careful teardown, also assembly. The video and audio were very good.

[@BrooksAirheadGarage]

Thank you Charles.

[@christianb4994]

Ich fahre eine R80 ST und habe dort auch die Siebenbrock 100 eingebaut. Die BMW ist so unfassbar simpel. Das ist es ja gerade was das Schrauben so schön macht. Ihr erklärt das wirklich sehr anschaulich und gut. Sodass sich auch die jüngeren da ran trauen. Meine habe ich dank euren Kanal komplett überholt. Endantrieb, Getriebe, Gabeln Speichen. Ja auch den Bosch Hallgeber. Also alles bis auf die Kurbelwelle und Pleuel war auseinander. Ich musste in den 42 Jahren noch nie in die Werkstatt. Vielen Dank für euren Kanal. 😊

[@longfellow5276]

I,ve had 5 Beemers in the last 40 years and the 75/6 was definately my fav. Great bike.😂

[@gravitygreg]

About to do this job tomorrow and happy to see you made a video on this install as well!! Well done. Thank you

[@BrooksAirheadGarage]

@@gravitygreg hope it went well! Take your time and everything will be great.

[@gravitygreg]

Thank you, I installed the cylinders, heads, rockers, set the valves, all the gaskets, o-rings, installed and followed the torque sequence. I rolled the engine over with the Allen key via the rotor a few times and everything was as smooth as can be. Installed the rebuilt gearbox, rebuilt mono-Lever, the rebuilt final drive. The gear box shifts smoother and better than anything I’ve tried before. I tore my hamstring in August and took on this project as I was off work for 3 months. I’m still off work (self employed) so I just keep working on the BMW. I break my day up with 6-8-12 hours on the bike 2-4-6 hours of watching your videos, (depending on the day) making step by step plans on 8x11” paper and then just doing the job. I have all the mental rehearsal done the night before. I clean up the garage space before I turn the lights out each night and set all the parts up for the next day so I have no hesitation, apprehension or doubt which might cause me to avoid working on the bike because of lack of confidence. I honestly could never have done this without you man! Thanks!

[@BrooksAirheadGarage]

@@gravitygreg You're welcome 🙂

[@michaelcrenshaw9199]

Excellent video. The Siebenrock instructions are pretty good. I installed a 1000cc kit to my R90/6 and it was a great upgrade. Im considering installing an 800cc kit to my R65.

[@BrooksAirheadGarage]

That should add some punch to the R65.

[@johannej3241]

@@BrooksAirheadGaragehi, I’m wondering if siebenrock has big bore kit for r60/2 like a 700 cc or 750cc? Thanks for the video and walking us through.👌

[@BrooksAirheadGarage]

@@johannej3241 I don't know if they do. You can visit their web site and see.

[@jtreg]

lovely. I would like that for my R80RT, great job Branden!

[@richardsalsman1069]

Timely, I am about to install a Siebenrock kit on my /7.

[@BrooksAirheadGarage]

Best of success. It went smoothly for Branden.

[@Aclan]

You're the best.By the help of your videos now I can completely tear down my 95 R80 GS and than fixed it and run! Thank you :)

[@BrooksAirheadGarage]

Thank you. I'm pleased this is helping you.

[@bunshoft]

Great father/son tradition, riding and wrenching together. I have a 1979 R65. Love the bike but performance was an issue so I put the Siebenrock 866 kit, a taller 5th gear and Mikuni carbs and it really goes like heck.

[@Markonthisworld]

Extremely comprehensive explanation, great to see you working with you son - I do similar now and my father helped me

[@BrooksAirheadGarage]

Mark, Indeed, Branden is getting to be a knowledgeable airhead owner, maintainer and rebuilder. 🙂

[@GanjaBaron]

Very nice! I'm replacing the pushrod tube seals on my R100R and this video covers that too.

[@WildlifeMoto]

Fantastic video gentlemen. Thank you.

[@BrooksAirheadGarage]

Thank you. 🙂

[@davesmith61]

Really good clear instructional video, thinking of getting an R75 & would probably go down this route if I do.

[@richardlaker9722]

Good morning Dave . Thanks for your message concerning my R45 engine upgrade to a 860. I brought the R45 as an insurance right off not structural enjoyed locating all the damaged parts. The engine upgrade is completed not by me . I was going down that route it all makes sense when I read your message. I won’t be getting the bike on the until 1st April so it gives me plenty of time to sort out the paperwork. It will be interesting to see wot they put in the V5. It will always be a R45 because the frame + engine numbers are still the same and the frame is small and shorter than the other models. Yer it’s quite an upgrade should be interesting 🤔 thanks again for your advice on this matter very helpful. Won’t be too long before we see some milder biking weather.🏍👍

[@abrahamlevi3556]

What an excellent video! One remark though: in some countries, however, this kind of conversion is strictly illegal as the only displacement allowed is the one that appears on the license. Although such infringement is undetectable during inspection, if God forbids there is an accident and the infringement is discovered, the insurance policy is no longer valid. In certain countries any modification that deviates from the license is strictly forbidden, so check beforehand.

[@nicolewiehle2492]

I don't think there is an insurance adjuster on the planet that could detect this upgrade.

[@scotfield3950]

Outstanding!

[@BWRBMW]

Apologies for the delay. The cost on the gasket is recommended by BMW. It may or may not help but it doesn’t help. An extra step that brings me a little peace of mind. I dumped the oil every 200 miles for 1000 miles during the break in. Sitting at nearly 5,000 miles on the new cylinders and no issues. Next step is to strap on our rebuilt 40mm carbs and matching heads to make it a nearly true R100

[@kevinschilling1368]

Excellent video (as always), thank you both,,,, great upgrade I'm sure,,,,,,something to ponder for my 1985 R80RT

[@BrooksAirheadGarage]

Thank you Kevin. 🙂

[@andrewdavis6917]

Great job, looks like a good time to me

[@BrooksAirheadGarage]

Thank you Andrew. 🙂

[@daledahlman9629]

Thanks for the thorough explanation

[@BrooksAirheadGarage]

You’re welcome Dale 😀

[@jimmycrowell8854]

212,000 miles "might be time for a top end refresh" gotta love old BMW motorcycles thats impressive german engineering

[@timlavance867]

For sure..I have 166,000 on my k75s runs perfectly..love it!!!

[@BWRBMW]

Well it had a top end at around 100k. Now that I put another 100k we felt it to be necessary.

[@scotfield3950]

Well done thank you!

[@BrooksAirheadGarage]

You're welcome. 🙂

[@vespasandengines]

Great video as always. Thanks Brook!!

[@BrooksAirheadGarage]

You're welcome.

[@christopherdopp8307]

Hi, I recommend copper anti seize, I used the aluminum version last time and it fuzed it all together and ruined the threads on the head. It was recommended that the compound be dissimilar to aluminum. Thanks for the video!

[@BrooksAirheadGarage]

Hmmm ... I've never had that problem with the silver anti-seize.

[@ryds1000]

Then you change from 750 to 1000 ccm. it is necessary to replace carburetor nozzles to some larger ones.

[@jasonochoochoski7442]

Thanks so much guys...

[@kenchan5624]

Excellent video very enjoyable very detailed thank you for both of you.keep up the great work.

[@BrooksAirheadGarage]

Thanks Ken. 🙂

[@ericwiltz6584]

First I wish you and your son a wonderful holiday and great 2024! GREAT VIDEO and hats off to using Three Bond is the only gasket sealant to use PERIOD, why not use grey? It also looks overkill to coat the gasket, (my opinion) You likely did this, but I always use a petroleum based degreaser on the inside of the cylinders and a white cloth to check for ANY residual, repeat the step until the white rag comes out white. Once clean, assembly lube immediately to the cylinder, just a thin coat, minimal. There is almost always residual material left by the hone even when cleaned by the factory. As for the assembly, nothing goes back together without using assembly lube.! Once you run this beauty, change the oil out to a synthetic called Trybodyne. It's pricey, but it's proven and you won't be sorry. Thank you for sharing this, Eric Harper, TX

[@ericwiltz6584]

Oh, anti seize on the spark plug thread.

[@robinoconnor1203]

That seems to be a lot of revs for a cold engine. I would be concerned about the extra power from the top end on a 200,000 mile bottom end. Around 1980, I put Krauser 4 valve heads on my R100rs.

[@garyhoward4064]

Why not take advantage of everything being open to also change the connecting rod bearings. So cheap and easy. Wonder why Siebenrock does not propose them together with the kit. I had to request them separately for mine.

[@timhayes7359]

Yeah good, but I thought you would have mentioned or checked the lifters for wear , especially for a topend build.

[@BrooksAirheadGarage]

They were perfect

[@scotfield3950]

What is the weight difference of the piston assemblies? One can offset this with typered piston pins

[@loop1479]

No mention of gapping the rings. I take it Siebenrock take care of this for us? One of the things I like about Bee Ems, so simplistic to work on. Thanks for the video.

[@frankcollins4743]

Simple, not simplistic. Different meanings.

[@trucktruck8016]

Sweet vid ,simple and to the point , looks an easy upgrade, though you didn't go into carb set up to suit the increased cc ?

[@BWRBMW]

Apologies for the delay. Increased the main jet one size is about it. Outside of that it was a standard carb balance per the bing book. Not much outside of that to run smooth. I’m at close to 5,000 miles since the upgrade and I have been very pleased. Stay tuned as soon we will be putting on 40mm carbs and matching heads to make it a nearly true R100

[@jeffshootsstuff]

What would you say to the people who are adamant that you should never use any silicone or any other goo/sealant on BMW airheads?

[@BrooksAirheadGarage]

In the case of cylinders you have to use sealant to prevent oil leaks.

[@stephenkramme7063]

Any thoughts on why the otherwise modern and up to date kit still uses a two piece oil ring? This seems like following tradition and very "old school" though it does work. How about a video that measures the clearances of the original cylinders, pistons and rings?

[@YOGiGrills-zd3zo]

Really special video, love you’re doing this with your son too. My dad built us some lovely R80’s and now looking at this conversion. How does she ride now? Is it a dramatic improvement in power?

[@BrooksAirheadGarage]

Branden says it has more punch now and he is happy with it. 🙂

[@YOGiGrills-zd3zo]

@@BrooksAirheadGarage thanks for the reply! If you get the chance would love to see a video of it being ridden or running 🏍️🏍️

[@BWRBMW]

Sitting at about 5,000 miles on the new cylinders. Very happy with the performance upgrade.

[@ekspatriat]

Surely the 750 heads have smaller diameter squish domes than a 1000. I believe that just fitting 1000 barrels and pistons won't match 1000 HP. Also would the valve diameters be different?

[@BrooksAirheadGarage]

Later on my son installed 1000cc heads and 40mm carbs. The 1000cc cylinders worked fine with the 750cc heads and 32mm carbs. Now there is more "kick in the ass" according to Branden, my son.

[@richardlaker9722]

Afternoon just wondering if you can help me. Ive just fitted my engine upgrade kit to my R45 very pleased. 👍 Question 1. Do I have to change the details on my V5 because the engine and frame numbers haven’t changed so it will always come up as a R45 . 2nd will I have to change the details on my insurance. Thanks looking forward to hearing any comments. Have a great Christmas. 🏍🎅🍺👍

[@BrooksAirheadGarage]

Richard, I have no idea about the answer to your questions. However, it's not uncommon for someone to upgrade a "stock" vehicle with modifications. The registration is still tied to the original vehicle.

[@davesmith61]

Hi Richard, yes you should let the DVLA know about the capacity increase, you need to send off your V5 & I'd be inclined to include a copy of the invoice for the kit & a covering letter explaining what you've done. Also you should really notify your insurers just to be on the safe side.

[@williamanderson4029]

So was there a noticeable difference in performance? did you rejet the carbs?

[@BrooksAirheadGarage]

Branden said the acceleration was noticeably stronger on his 10 mile ride. Currently the jetting is not changed, but he will check the plugs to see if jetting changes are necessary.

[@BWRBMW]

Quite a noticeable difference. I have a bit better then 100 miles now and it definitely has more get up and go. The carburetors required larger (135 to 150) jets and opened the needles up by one notch

[@assessor1276]

Nice work and as always, an informative video!

[@loop1479]

@@BWRBMW Is yours a R75 conversion as well? Thanks

[@BWRBMW]

@@loop1479 yes I should have clarified. I’m Branden, that’s my motorcycle.

[@MwenjeNgambi-hp7nw]

hi l like this do you sell second hand parts

[@BrooksAirheadGarage]

No 😊

[@DAM-n7j]

Have you got a later model gearbox on this bike? Curious to know how the swap went? Also is that an extended sump? cheers!

[@BrooksAirheadGarage]

When I had the transmission rebuilt by Tom Cutter, he replaced the case with a used newer one since one of the clutch cable tabs was broken. It does have a deep oil pan that I installed in the early 1980's.

[@DAM-n7j]

thanks for the reply. Seems like you really have the best of both worlds now - older styling and 'modern' performance @@BrooksAirheadGarage

[@DAM-n7j]

A question about the siebenrock swap - did you base gaskets have clearance for the o-rings to seal against the engine hosing or did they seal against the base gasket ? I am at this stage myself with the same kit for my R75/6 but I have some base gaskets from earlier. They look like the same ones in the kit that siebenrock supplies but I can't be sure. thanks!

[@BrooksAirheadGarage]

The orings seal against the cylinder base and the hole at the top push rod in the engine block.

[@DAM-n7j]

right so the hole in the base gasket was large enough for the o-ring to pass through and seal against the engine block? sounds like I might have the wrong ones @@BrooksAirheadGarage

[@loris199]

Awesome video! Makes me want to try to do the same on my R80GS (already have the 1000cc SR cylinders and pistons inside). Job seems not too trick. Do you recommend me to try even if i have close to 0 experience?

[@BrooksAirheadGarage]

loris199, I think you can do the upgrade without large amounts of experience. I have documented installation of the top end on different bikes on my web site: brook.reams.me. You can look at them as well as this video. I also have posted other videos on installing the top ends, but for newer airheads that don't have the base gasket. That's the main difference with this 1975 R75/6.

[@loris199]

@@BrooksAirheadGarage thank you so much for the feedback, i'll go for that...if you never try you never know Cheers from Italy and thank you again for your precious contents

[@BrooksAirheadGarage]

Best of success 😃

[@halukalpkaya7895]

1988 yılında polisten çıkma 1976 model R60/6 yı 94 mm silindir ve piston takarak 1000CC ye yükselttim. Komprosyon oranı aşırı yükseldi ve sürekli detenasyon yaptı. Orjinal silindir kapaklarını takarak sorunu çözdüm. Sonradan karbüratörleri de değiştirdim. Buna rağmen özellikle şehir içinde çok ısınıyordu. Max hızı 2 kişi ve çantalar ile 195 Km/saat yakıt tüketimi max yükle hızlı kullanımda 100Km/7Litre oldu. Frenler ön dahil kampana idi kesinlikle yeterli değildi. Siz komprosyon olayını nasıl çözdünüz? 63 yaşında Otomotiv teknik öğretmenim (yüksek okul) BMW nin bu serilerinde sabit strok 72 mm idi yaklaşık sanıyorum 74 94 mm arası silindir ölçüsü kullanarak hacim büyütmek ne kadar mantıklı bilemiyorum. BMW nin en muhteşem eseri 1962 1968 R60 serisidir. Özellikle R69 S 42 PS. Amerika için üretilenler değil. Orjinal ön takım beşik amortisörlü olanlar. Her yük yol ve fren durumuna göre kaster açısını sürekli değiştirerek mükemmel yol tutuş sağlar. R90S lerde fena değildir 67 PS Türkiye den selamlar.❤❤❤

[@jamesconnors4297]

revving that high with a new set of pistons and rings would have me cringing tbh.

[@BrooksAirheadGarage]

James, Bob Fleischer (aka Snowbum) recommends this so the rings seat into the bore quickly so they are oil tight.

[@CharlesStettler-kp4ot]

pojj

[@gustavbohner7123]

Deutsches Motorrad auf Englisch kommentiert geht garnicht 😢😢😢😢