Topic: my cb550 vs BMW R75

[orange550]

I love my 74 CB550, but I have an itch to buy an older BMW airhead. I did a longer road trip with my 550, and while it was great, I think I'd like something a bit more suited to long trips...(but I still want something classic and stripped down looking). Looking at a 75 R75/6. I like the early R75 (with combo headlight & speedo) but I read about transmission issues with the 4 speed. Also looking at a few R100, some RT versions & some stripped down & basic. I don't want a fairing just yet.

Anyway, the R75 has the same hp rating as my 550, but at lower rpms. But it has a higher torque rating at lower rmps then the 550. I wonder if the R75 will "feel" like it has more power then my CB. I really enjoyed tripping my 550, and there is something very cool about doing long distance on a smaller bike like my CB... but / plus if I'm thinking R75, I wonder if I should just go to a R100.  (or a coveted R90 if I can find one).

Sorry if this is the wrong forum to post, but I was hoping to get feedback from riders that had experience with both the CBs and the old Beemers.

[Chris_SZ]

Hi.

I had a 60/5, a 100S and have now a 80 RT. The CB550 here is pulling a sidecar, so a direct comparision isn't easy. Compared to the SOHC/4s the airhead is a chunk of scrap metal, it rattles and changing gear is more often than not accompanied by a loud "clonk". However, a bit training and you can switch gears as silent as with a Honda. The nice thing is that you have torque from lower revs and cruising is at lover revs as well. Noone in your neck o' woods who would give you his for a ride, just to find out?



Servicing the BMW is much easier as all valve tappets are easily accessed from the sides. Get one with electronic ignition, adjusting the points which are located below the generator, just behind the front wheel is a bit tricky  . But then, you only have one point 

OTOH the 4 cylinders run smooth, more like a turbine compared to the 2 mug-sized airhead piston vibrator. If I had to choose, for a 500+ miles trip I would always take the BMW.

Just my 2 cents (€uro)

[Lil Red]

The beemer will feel like an old uhaul moving truck compared to the CB. though the performance envelope might very well be comparable in terms of absolute time and g's etc.

My experience with the R100 was like that. I rode the RT and the RS...the R75 might even be more agrarian. Not that it was a bad experience...as it may well suit you for the way you intend to ride it. The RS certainly has a cache to it...with the fairing and ergos..it was a unique and satisfying ride even though it still had a quite a bit of " I'm a very style-eesh east German border guard feel to it. I was also shocked by the amount of shaft jacking was present...They dont encourage high rpm operation but like a straight 6 pick up just kind drive well without much shifting...just dont expect much excitement.

Now for my completely biased opinion, look at 70's vintage Moto Guzzi T-3's G5 or an 80's Strada....they are few and far between and come with their own set of idiosyncrasies, like rare dealerships, and lack of "official support", but there is strong grassroots support and plenty of mail order parts availability. The old Guzzi's have unique charm and character all there own, and a sound unlike any other bike. A Very nice balance...Decent brakes, which are linked like some Hondas...like my CB400f , they have a certain Walter Mitty quality to them that makes you feel like you're a much better rider than you actually may be...something I didnt get from BMW's...

Go ride a few of both and see how you feel, Beemers and Guzzis Are like dog whistles...you may very well ride an old toaster tank beemer and feel like it's where you've always belonged...

Oh and Guzzi's encourage high Rpm hi jinks ( 6-7.5K) along with strong low end and are very robust for something Italian...

[steam-powered man]

i have an r75/6, had a cb550 ( and a bunch o' others over the years).  have had my r75/6 since 1980, and never, ever not started nor left me stranded.  i'd stay away from the 4 speeds btw.

engine/trans -- power rating is low, revs a little slowly, and shifting is wonky.  (ka-chunk!).  some day you might get used to the bike rocking a little as you blip the throttle due to the engine layout.  as with any non-faired bike, windblast is the only limiting factor for cruising speed.  it'll travel all day at 70mph if you'd like but it's tiring.  top on mine is 110 indicated, in prone position (think rollie free).  periodic maint is stupid easy.           

handling/brakes -- with modern tires, turn-in and mid-corner stability is very nice.  i'd recommend progressive springs and experimenting w/different fork oil weight for damping.  regarding brakes, they were adequate for the time.  with a new brake cable and ebc pads, i can dive the front end pretty easily, but takes 3- 4 fingers.

ergos -- even with my "S" Magura bars, the ride position is upright, comforable.  the seat is perfect, not too hard nor too plush.  they got it right.  much is made of the blinker switch position, it's nothing.   

expect the same power characteristics if you move around to the r90, r100 etc.  i've heard that in much later years bmw shifting has improved so it's less clunky.  bottom line is that any early "R" will accelerate somewhat slowly, shift a little klunkily, brake adequately and probably outlast you.

[grcamna2]

I've ridden and wrenched on a good few BMW airheads and I've ridden them on very comfortable ;)extended test rides...didn't want to come home .The layout of the footpegs and seat w/ the standard bars is just perfect for a nuetrel riding position and won't tire you out for MANY miles;lot's of guy's get the transmission gears undercut and once that's accomplished it will shift VERY well and stay in the upper rpm powerband nicely...a good strong boost of twin power up there too.They are meant to last a lifetime w/ good preventative maintainence.

[simon#42]

well i have a 75/5  and a 750f2 , and love them both . for long distance nothing beats the bm , it will cruise along at 85 all day , has a 250 mile tank range and is totally reliable . the four speed box is pretty clunky , even compared with the f2 which isn't that good itself . the latter bm boxes are better but for best results you need a post 81 flywheel with a mono arm box [ ive simplified this but you get the gist ].
dont read too much into hp figures bm's go alot better than there power outputs would have you believe . if i could only have one it would be a difficult choice ....... lucky i dont have to make it .  if you can borrow a bm [ any of the airheads feel similar ] take it on a long ride , they feel strange at first but after a few mies really grow on you.

[grcamna2]

+1 .

[Roach Carver]

I have a 75/5, a 75/6 and an r100. Have not ridden the 100 much. Love both my 750s. They are high quality machines. Dont fear the 4 speed. The main trans to have issues were in 1974. First year for the 5 speed. Fourth gear has poor wear. Get one. You wont regret it.

[simon#42]

yes it is the first of the five speeds you have to watch out for, i have never had any problem with my four speed box and it has the advantage of making one less clunk .
if you really want to know the ins and outs of air cooled boxers this is a great site

http://bmwmotorcycletech.info/technical-articles-list.htm

[orange550]

Thanks for all the various input. This is exactly what I was looking for.

I know the airhead won't be as zippy as my 550, but that's not what I'm really after. I just want a bit of an alternative for longer distance riding, but still remaining in the classic bike territory. I know hbp numbers on paper are not really indicative of how a bike feels on the road, but I really do hope to get more "torque feel".

I'm looking at a 1975 r75 which is the second year of the 5 speed, although I've read (thanks to the links provided in the this thread) that the early 5 speed issues carried over into some of the early 1976 models. I wonder if I can get a build date from the VIN.

I'm also looking at a few 75/5 but would worry about the short wheel base version and the 4 speed. Although as some have mentioned here, the 4 speed is not as bad as its rep. The front end on the 4 speeds is awesome, but maybe it's not worth it, if the 1975 and later models are far superior in other ways.

Thanks,
Chris

[Roach Carver]

I love my /5 and would not hesitate to ride it all day long. The first thing is to find one you like. Fact is, theyre all good.

[orange550]

I think I read that 4th gear in the /5 is the same ratio as 5th gear in the /6. So all you're getting is less spacing between gears?

Is this correct?

(oh and Roach Carver is your /5 the long wheel base 1973 1/2? but some people changed them on the early ones )

Thanks,
Chris

[Roach Carver]

I have a swb. Early 71. Never given me any trouble. The front drum is so-so but set up properly im told that they work as well as a single disk.

[simon#42]

i have a short wheelbase 71 as well , having owned a r100/7 and ridden many other bm's i recon the short one handles much much better . there where rumours of instability problems but i must admit i have never talked to an owner that had actually experienced them , Roach Carver how do you find yours?

oh and yes top gear in both the 4 and 5 speeds have the same ratio

[Roach Carver]

I have'nt put a ton of miles on mine. I have more experience with my /6, but my swb has never given me the slightest inclination that it wanted to wobble or anything else. I think most of this is symantics. Back in the day I am sure everyone went gaga over the 5 speed, and disk brake as that was the latest- greatest. I assume for the most part we all ride these for the same reason. Its kind of nostalgic and I doubt that one compared to another would be discernable or less fun to ride if both were in good condition. Now compared to a liter sport bike.... that would be a noticeable difference. Like I said, find one you like and I think no matter what you get, you will be happy.

[orange550]

i have a short wheelbase 71 as well , having owned a r100/7 and ridden many other bm's i recon the short one handles much much better . there where rumours of instability problems but i must admit i have never talked to an owner that had actually experienced them , Roach Carver how do you find yours?

oh and yes top gear in both the 4 and 5 speeds have the same ratio

Hey Simon,

How well does your front drum brake work? Assuming it's set up correctly is it almost as good as a single disc on a CB. (my 550 has a single disc and it ain't great. can't imagine a drum being a whole lot worse)

[simon#42]

not great to be honest , ive tried the standard linings and they left alot to be desired , then had the shoes relined with a softer woven material which was better but still not great . have just had a set lined with what they describe as a race compound , am putting some cartridges in the forks at the moment when i am finally finished i will give them a try .
there is not much to set up on the drum so if this doesn't  work i will make some longer brake arms .
its been a while since ive ridden a cb with a single disc but from memory as standard it is probably about the same .

get your money out and buy one orange ........ you know you want one !
boxer prices over here have started to go up recently , might get another myself while they are still reasonable

[orange550]

Yeah, I'm pretty committed at this point. It's between an early /5 or a nice '75 R 75 / 6 that I found. I love the front end on the /5, but dig the 5 speed and disc on the /6. It'll come down to which one is in really great shape.

I do plan to do some heavy modding which will make the airhead purists head's explode. That will be fun.

My dad will be glad I bought one, but will be confused that I chopped off the rear fender.