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Old 06-13-2012, 02:08 PM   #1
Maxhr190 OP
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R100 handling characteristic

How should a R/100 handle?. My 83' has no steering damper ( previous owner removed), on tight turns both left and right, the steering is not very neutral, the front end wants to oversteer. I have 'S' bars installed. The bike tracks straight however.
Thanks
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Old 06-13-2012, 03:18 PM   #2
Tosh Togo
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Quote:
Originally Posted by Maxhr190 View Post
How should a R/100 handle?. My 83' has no steering damper ( previous owner removed), on tight turns both left and right, the steering is not very neutral, the front end wants to oversteer. I have 'S' bars installed. The bike tracks straight however.
Thanks
What tires/what sizes/tire pressure on both ends when it misbehaves/how many miles on the tires....

btw- when the front end tries to go walkabout/ go wider in the corner, it's called understeer; it's only called oversteer when the other end wants to do more than asked for.
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Old 06-13-2012, 03:19 PM   #3
supershaft
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Oversteer? Most would take that to mean that your back tire is stepping out. That just means you are hauling ass.
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Old 06-13-2012, 03:28 PM   #4
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The tires are new, metzler lazer tec front/rear, air pressure is whatever owners man. Spec.
When I say oversteer it does more than asked for. I also own a 79R/100 that corners very nimble. I will check specs. Maybe the rake is more relaxed on the 83'
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Old 06-13-2012, 03:42 PM   #5
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Originally Posted by Maxhr190 View Post
The tires are new, metzler lazer tec front/rear, air pressure is whatever owners man. Spec.
When I say oversteer it does more than asked for. I also own a 79R/100 that corners very nimble. I will check specs. Maybe the rake is more relaxed on the 83'
That's what new tires do. There profile is still round. The rake is the same on all airheads frame wise. You might have a bit different effective rake for running different sag, etc. but . . . . Lazer tec's? I can't get those to last more than 1,500 miles in back. One time I wore a brand new one down to the wear bars in one day. No joke! That was my only 1000+ mile day. It was hot and I was hauling the mail but still!

The book might be a bit low. Most people are running entirely too much pressure these days IMO but . . . .
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Old 06-13-2012, 05:55 PM   #6
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I have metzler lazer tec front and back that I inherited from the PO. Got over 10 000 km's from them so far , which included a 4000 km's (2500 miles) in three day trip. I was meant to replace the rear 3 months ago ... but after every trip now I look at them and think ... maybe I can get another 500 km's out of them.

I can feel a " Days of Thunder " moment coming on.
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Old 06-13-2012, 07:41 PM   #7
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Perhaps the rear shocks are stiffer and set the back end up? Or maybe the fronts have progressive springs in them?

Do you have the correct amount of sag? How does sag compare with your other bike?
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Old 06-13-2012, 07:41 PM   #8
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try running your tyres at 36 front and 38 rear, makes a huge positive difference on mine from running lower pressures, remember the handbook is the same age as the bike not the new modern tyres.
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Old 06-14-2012, 12:22 AM   #9
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Quote:
Originally Posted by Maxhr190 View Post
How should a R/100 handle?. My 83' has no steering damper ( previous owner removed), on tight turns both left and right, the steering is not very neutral, the front end wants to oversteer. I have 'S' bars installed. The bike tracks straight however.
Thanks
As has been said before, front ends don't oversteer. Oversteering is where the back end slides out from the front end
Like flat track, dirt track, outlaw or drifting.

Understeer is where the front end "pushes" so that even when you are turning the bike is heading to the outside edge of the corner. Like driving a front wheel drive car, in the snow.

But handling, it's way more then just tires or a lack of steering damper.
How's the suspension? including all pivot points?
Are the wheels in good nick? Decent bearings?
Are the forks in the triple clamps straight? Fork tubes straight and non binding, there should be only a slight amount of stiction.
Are the handle bars bent?

BMW's earned their reputation as rubber cows for a reason.
Softly sprung suspension, long bikes, carrying a lot of weight, shaft drives, flat twins with a crank that turns in line with the frame all add up to some possible funky handling, mix this with old bits and they can be a handful

These bikes respond best to smooth operator movements with a steady increase of throttle through a turn.
Rolling on and off of the throttle will upset the handling something fierce especially for someone coming off riding a chain drive in-line 4 bike.
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Old 06-14-2012, 01:30 AM   #10
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I had a similar situation on my G/S. I changed the front springs for new (progressive) ones and it dramatically improved the way she would turn in (much more gentle), and held the line.

Also noticed more stable in a cross wind at speed (ie freeway)
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Old 06-14-2012, 11:03 AM   #11
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I still have a feeling what max is talking about is the new tires. New tires and/or different tires can completely change the way your bike turns in or change it just a little bit. It all depends on the tires.

Heavy BMW's? They are around 100lb's lighter than most bikes in their class that had much reliability. As short of shorter than a lot of them too.
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Old 06-14-2012, 11:56 AM   #12
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Originally Posted by supershaft View Post
I still have a feeling what max is talking about is the new tires. New tires and/or different tires can completely change the way your bike turns in or change it just a little bit. It all depends on the tires.

Heavy BMW's? They are around 100lb's lighter than most bikes in their class that had much reliability. As short of shorter than a lot of them too.


When was the last time you saw a BMW that didn't have an extra 100 or more pounds of stuff loaded on it?
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Old 06-14-2012, 12:12 PM   #13
supershaft
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Every time I look at one of mine! Sometimes I forget what a rare breed we are. SO many bikes look like you drug a magnet through a junk yard!
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Old 06-14-2012, 12:31 PM   #14
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I had a customer come in complaining about "wobbles". R100/7, saddlebags,tank bag, top box, all loaded with "stuff" 20# pressure in the cupped front tire and 13# in the bald rear. It was difficult to convince him that I may have found his problem.
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Old 06-15-2012, 12:25 AM   #15
squish
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Quote:
Originally Posted by supershaft View Post
I still have a feeling what max is talking about is the new tires. New tires and/or different tires can completely change the way your bike turns in or change it just a little bit. It all depends on the tires.

Heavy BMW's? They are around 100lb's lighter than most bikes in their class that had much reliability. As short of shorter than a lot of them too.
Back in 83, there were a lot of bikes that had much better reliability then the airheads.
It's a stretch to say the BM's were around 100 lbs, more like 30-50 lbs lighter but down some 20 to 30 horsepower.
In my book, that's heavy.

Remember this was the height of the superbike wars and you could get some pretty cool bikes from Japan inc by this time.

The 83 R80ST held the claim at that time of being the lightest bike in 800cc class. Yet much of the Japan inc bikes would out run the ST easily and the ST was thought of as being the "best" handling BMW to date.

As for tires, sure new tires can easily screw up the feeling of a bike. but 29year old suspension bit's can also do it.
Especially those bits on bikes that were never known for their razor sharp handling.
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