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/2 Sidecar combination?

eagan7096
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Joined: Fri Oct 27, 2006 3:00 am

/2 Sidecar combination?

Post by eagan7096 »

Hello,
I recently purchased a 66 R69S with a Steib TR500. I'm interested in everyones opinion about whether the R69S is adequately powered for this sidecar and what are any recommendations for improvements? Also are the stock brakes sufficient?
Thank you,
Earle
Earle Eagan
57 R69

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schrader7032
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Re: /2 Sidecar combination?

Post by schrader7032 »

I'm the last person to weigh in on this, but I'll try! I'm not sure power is the deciding factor here. The R69S is more powerful than the R60/2 and R50/2 but it is my understanding that the R60/2 was usually the most likely bike to have a chair attached. The R69S had higher compression engines and I could see where with a chair attached, that restricts the air flow on that side, making that cylinder hotter.

One thing needed...although I've seen people say it's not necessary...is a transmission that is set up to have a first gear ratio that is better suited for pulling a sidecar. Typically the non-sidecar transmission had the letter "S" stamped near where the speedometer cable attaches. The "S" didn't stand for sidecar, it meant a "sport" transmission gearing.

As for brakes, I think they're barely adequate. But I think when someone is driving a bike with sidecar, you have to dial back your expectations and anticipate your reactions sooner than normal.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

mcsherry1328
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Re: /2 Sidecar combination?

Post by mcsherry1328 »

In my opinion all the /2 models are all right for sidecar use. Gearing is most important. I have an R69S with Steib S500. I have had this rig for forty years. It works great with R69S engine, I chose this model for the extra power. I have the standard S stamped sport gearbox which works fine. My biggest recommendation is using a 27/7 ratio rear drive. The rig walks away from stop just off idle and cruises fine at 65 mph. I have no desire to go faster than that, the bike is capable of more.
For the R50 & R60 the 26/6 ratio rear drive was recommended . When I first set my rig up I used the 26/6 and for me it was way too low geared. At 60 mph the engine was spinning too fast. The 27/7 ratio works perfect. As for brakes, all /2 brakes are barely adequate but work good enough for me. I had the brake shoes upgraded to a higher performance material which helped a little.
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Daves79x
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Re: /2 Sidecar combination?

Post by Daves79x »

BMW 'recommends' the 26/6 ratio for the R50 and R69S and the 27/7 for the R60. Everyone has their own experience. I personally think the 27/7 is the best for most applications. Problem with changing to any final drive ratio other than standard is the speedo does not match, and you'll never find the correct ratio speedo in mph.

My solution was to change an S transmission to the sidecar ratio. The R26/27 trans has the correct sidecar ratios and the gearsets swap right out. The standard speedo can then be used. I have the sidecar ratio transmission in my '55 R69 (the early bikes came that way). First through third gear are all lower than the S transmission. I've not pulled a sidecar with it, but the first two gears are creeper gears and it should work fine. I'm building a basket R60/2 with this transmission to haul a TR500.

Dave
Dave

mcsherry1328
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Re: /2 Sidecar combination?

Post by mcsherry1328 »

You are quite right on the speedo issue. I'm not much concerned about the speedo with mine. I know mine is about 5 mph off & I really don't care much about that. For me the rig works great and I can cruise at highway speed all day and the engine speed is perfect .

dosgatos
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Re: /2 Sidecar combination?

Post by dosgatos »

The 27/8 final drive from the US models is an excellent choice for sidecar use. The correct speedo for this is 1.23, but I have found the 1.2 is very close, having checked my indicated speed against a number of speed check trailers often used by municipalities. My R60/2 accelerates from a standstill (even on a hill) without slipping the clutch and will maintain 60-65 without effort. I've had it up to 70, but don't feel comfortable at that speed with a sidecar.

R68
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Re: /2 Sidecar combination?

Post by R68 »

I have an R69S with Spezial-TR500 mounted. I have a 26:6 ratio final drive, and 1.44 ratio speedo. I'm using a solo gearbox, the factory recommendation for R69S. The 26:6 final drive ratio is too low, the motor revving to high to get above 50mph or so. I'd take dosgatos excellent suggestion and try to find a 25:8 ratio final drive, or a 27:7 sidecar ratio final (expensive) if feasible.
Generally, it I think putting a sidecar on an R69S is like putting a cart on a thoroughbred. I'd advise finding an R60 or R60/2 for the project. No, the stock brakes are not sufficient for most modern USA use. The accessory ATE hydraulic brake for the sidecar cannot be made to function. Delete the hydraulic steering damper. Invest in 26" sidecar handlebars. Keep the bike a light weight as possible: no big tank, big seats, luggage carriers, panniers, fairings, passengers in the sidecar, etc...

dosgatos
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Re: /2 Sidecar combination?

Post by dosgatos »

I completely agree with R68. The R69S was a "sport bike" in its day. The torque of the R60/2 was appropriate for sidecar use. I have a R60/2 with a Bender LS sidecar (Steib S350 copy). It will do 65 mph while breathing hard, handles marginally at that speed, and stops reluctantly. I also stay on secondary roads.

Motorcycling has its share of wild men. I saw a R60/2 conversion with a R90S engine, complete with Dell'Ortos. The owner bragged about being able to exceed 100mph with this outfit. I've owned a R90S and had it up to an indicated 120 once. I can't imagine it doing over 100 with a sidecar, and wouldn't want to be on it if it did.

Cgollmd
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Re: /2 Sidecar combination?

Post by Cgollmd »

Good afternoon and I apologize if I'm hijacking a thread or if it's too old. I recently acquired a 1961 R60/2. VIN 622752. I'd like to find a good sidecar for it. Can anyone tell me how I can determine what gear ratio I have in this bike? I have read the thread on different opinions on what's "optimal". I mostly ride in Florida so hills might not be as much of a concern for me.
1961 R60/2

Daves79x
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Re: /2 Sidecar combination?

Post by Daves79x »

You likely have a 25/8 final drive (it's stamped on the input housing) and a solo transmission (S stamped on the speedo cable housing on the transmission. I think many guys find that OK for level ground, but you'll still struggle to maintain speed in high gear. BMW liked the 27/7 final for the R60. They are hard to find used and new crown sets are pricey. Then you have the miss-match speedo issue. A sidecar transmission is a good option, but hard to find and $$$. Lots of info on this topic out there.

Dave
Dave

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