Gut feeling or "60 horses and a duplex front brake"

[Major Softie]

I don't get the importance of matching numbers . . .

I kind of get it Chuey, or at least I think I do. My take is that Stephen is not enamored with matching numbers. However he is enamored with getting maximum money when he goes to sell the bike
Ken

Resale resale resale. That's the only time matching numbers matter. And, the older the bike is, the more it matters to value. Right now it isn't a big deal to most /5 buyers, but it matters to some. Now, for a /2, matching numbers are at least a $1500 item for R50's and R60's, and it probably makes a difference of over $2000 on an R69S. It won't be that terribly long before those numbers will begin to apply to /5's.

[StephenB]

My take is that Stephen is not enamored with matching numbers. However he is enamored with getting maximum money when he goes to sell the bike.

Right on the button, Ken. Just like Max said:
"If anything were to suddenly cause my demise, my surviving wife or family would have no problems when selling my bikes by unintentionally misleading potential buyers with a misrepresented machine. "

Right then, Max, the 308 is the standard cam so you're suggesting an upgrade to either 750 (which is what I have) or 900cc without touching the cam. Makes sense and I like it. It also is a money-sensitive solution. The 900cc engine is the only engine I never experienced.

I did build a "Best of 33yrs Airheads" Frankenbike and dubbed it R100G/S. It was great fun to build and has many very unique features. Been there, done that, worn the T-shirt.

Stephen

[Garnet]

IF this may be your only bike in the future then don't worry about the front drum. It has plenty of power and gets better when hot. The biggest problen with it is, when you regularly ride a bike with a two finger front brake, it is hard to like the grip you need to stop a front drum. But it will stop, and well. Just go over to the raceing forum and check out Stan's R75 race bike. He has Ferodo shoes on it now, but he raced it for a couple of years with a STOCK front brake.


Also IF this will be your only bike in the future go big CC but not big cam. A stock 900 is a very fun bike, lots of bottom end and lots of get up and go, so you can ride lazy or fast on the same bike. If you don't have a line on 900 jugs already take a serious look at the Sibenrock 1000cc kit for bikes up to 76. They claim 64 HP with no head or block mods.

The 780 Euro price tag is a bit of a shocker, but used 900 jugs cost a few bucks, and will probably need to be rebored..... then check out what oversize 900 pistons cost, gulp. The money you will save on staying with a 308 cam and oversize pistons will get you most of the way there.

[Sam LP]

I'd go for the 750cc engine, standard cam. I worked in the bay area in 1993 and was lent an R75/5 SWB.
That bike accelerated, braked and handled really nicely. The only difference from stock was 34mm Mikuni carbs.

Sam

[Duane Ausherman]

My shop raced a R75/5 in production class. It had the 336 cam, some minor head work, but stock higher compression 750 pistons. It ran quite well and in 73 won the Oregon class for both prodution and GP for the year campaign.

One Sunday I rode it on a Northern Ca BMW club ride. It was "sort of" street legal and of course I just used the dealer plate. It was not much fun to ride, as it was too hot and hard to keep in the cam range. Last time I rode it on the street. It would have been far more fun to just go riding by myself.

[StephenB]

Thanks for your input, guys. Seems I will be watching the usual sales channels for 900c pistons, barrels and heads, The existing 750cc parts will be my fallback option.

[Motorhead]

You could ask me that question
Matching numbers and Mods to the point of what bike and part will I need to fix it when it breaks

Matching number is where it came from and what it was....

the 900cc with a drum brake will work -IF- the brake is set up proper AND a bike set up as period fitting is the lightest BMW
SWB verses LWB add a second top plate for stiffing the front end

My 1973 R75/5 is a 900cc upped to 1974 spec

Motor is spec'd to a R90S top end with Mikuni round slides and 312 cam

brakes twin ATE 40mm with a early pre switch master plumed to a tree to twin
and rear Brembo

Snowflake Mags

recently my rear master is leaking and I'm thinking of returning to drums so If you decide you need the exta power of Disc contact me

Bike is faster and breaks very well

[StephenB]

Thanks, motorhead, but I'll stick to the drum. If and when I went some reasonable 900 parts I'll go for it. Have it on the slow burner due to shortage of significant funds.

[Zombie Master]

Who cares about collectors? If you don't intend on selling this bike make it what you want. When was the last time some one cc'd a bike you were selling anyway. But IMNSHO I would enhance throttle response, rather than go for horsepower. No matter what you do the bike is still going to be slow compared to modern bikes. So I would concentrate on the natural feel of a healthy boxer and attempt to enhance its "groove" so to speak. Brakes will never be more than adequate unless you do a radical change. Keep it real! Stay within the parameters of the Fatherland!

[Ridercam]

Who cares about collectors? If you don't intend on selling this bike make it what you want. When was the last time some one cc'd a bike you were selling anyway. But IMNSHO I would enhance throttle response, rather than go for horsepower. No matter what you do the bike is still going to be slow compared to modern bikes. So I would concentrate on the natural feel of a healthy boxer and attempt to enhance its "groove" so to speak. Brakes will never be more than adequate unless you do a radical change. Keep it real! Stay within the parameters of the Fatherland!

Ride your bike the way it is. Forget about performance. I did that route several years ago by putting a r100 into a toaster 75/5. The thrill was more on a straight run and talking to folks who cared about the make. Finally, the amount I got back when I sold the bike was equal to the parts I put in and in the motor exchange. As collectables, a rubber cow is what it is. let someone else worry about worth after you pass. Until then ride it as is and properly tuned. It is a little big bike with all the excitement and challenge you care to throw at it. Take the money and ride it in a closed course. there you will build a good story.