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Old 04-07-2014, 12:47 PM   #1
Buckslip OP
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Shocking advice for a noob

Okay, so first time on the forum please be gentle. I've ridden for a while but never an 'older' bike. My darling wife bought me a converted 81 R100rs for my 40th. The previous owner/converter was more into form than function so while it looks like a great cafe racer it's a bitch to ride. A local mechanic has sorted out most of the balancing, replaced the front discs with ebc's etc but the ride is awful. I think he's used a cheap rear shock (def not the originals) and the front end it so stiff if i hit a slight indent on the road it feels like my vertebrae is going to shoot out of my neck. Being at the tip of Africa parts are limited here (as is money) so but I can import (at a vaguely reasonable price) a pair of Hagons for the rear but I'm not too sure what to do about the front end. Progressive springs? I noticed a bit of weeping at the top of the forks, could this be the cause of a stiff ride? Any basic help would be greatly appreciated. You can laugh at me too, I have to start somewhere...
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Old 04-07-2014, 01:00 PM   #2
100RT
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Front forks may have too much fluid or preload. May have a stiction problem due to alignment issues. Progressive springs can be harsh. Check the rear shocks for any preload asjustment and back it off if it has a way. Get a manual to guide your work.

You need to find out exactly what you have to work with first.
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Old 04-07-2014, 01:24 PM   #3
Dmaster
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Quote:
Originally Posted by 100RT View Post
Front forks may have too much fluid or preload. May have a stiction problem due to alignment issues. Progressive springs can be harsh. Check the rear shocks for any preload asjustment and back it off if it has a way. Get a manual to guide your work.

You need to find out exactly what you have to work with first.
At the same time, progressive springs can be soft, linear springs can be harsh and soft as well.

-----

How does things feel if you push on the forks? Can you push some stroke? Does is has sag? (without rider), stiction?
And the rear, does it has sag? (without rider!) does it come up quick?
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Old 04-07-2014, 01:50 PM   #4
Rob Farmer
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Sounds like the wrong fork oil. 7.5w gives a decent ride in your forks. If it was an RS and has had the fairing removed the springs will also be very firm. The unfaired bikes have a slightly longer, softer spring. Whatever you do don't buy motorworks progressive springs.

Hagon shocks are awful. A pair of ikons would be a much better option.
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Old 04-07-2014, 01:53 PM   #5
Warin
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The harsh feel is probably too much 'damping' - the oil is too 'stiff' (too high a viscosity) or someone has changed the restrictions that the oil flow through. Simplest thing to do is change the oil in the forks for 5 weight. At least this way you'll know what is in there (both quantity and viscosity). {edit} When you remove the old oil - measure the quanity, and store it for a while until you have a good idea of what effect the new stuff has had on the ride. {/edit}

Springs? A quick rough measurement of the amount of 'sag' when you sit on the bike will give you an idea of how 'stiff' these are. you want about 20 to 30% of the suspension travel used up when your sat on the bike compare to when none of the suspension travel is used up.

Why do people do this- go for stiff suspension? Because they think it makes the bike go faster . The truth is it makes the bike go slower ... just dumb people who cannot think.

Warin screwed with this post 04-07-2014 at 02:00 PM
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Old 04-07-2014, 09:48 PM   #6
bmwhacker
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Quote:
Originally Posted by Buckslip View Post
Okay, so first time on the forum please be gentle. I've ridden for a while but never an 'older' bike. My darling wife bought me a converted 81 R100rs for my 40th. The previous owner/converter was more into form than function so while it looks like a great cafe racer it's a bitch to ride. A local mechanic has sorted out most of the balancing, replaced the front discs with ebc's etc but the ride is awful. I think he's used a cheap rear shock (def not the originals) and the front end it so stiff if i hit a slight indent on the road it feels like my vertebrae is going to shoot out of my neck. Being at the tip of Africa parts are limited here (as is money) so but I can import (at a vaguely reasonable price) a pair of Hagons for the rear but I'm not too sure what to do about the front end. Progressive springs? I noticed a bit of weeping at the top of the forks, could this be the cause of a stiff ride? Any basic help would be greatly appreciated. You can laugh at me too, I have to start somewhere...

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Old 04-08-2014, 12:15 AM   #7
Buckslip OP
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Pics

Thanks for the replies so far. I'm attaching a few pics of the front and back shocks and a sort of close-up of the top of the front forks which appears to weep after a ride. There appears to be no branding on the rear shocks which makes me think he replaced the original with 'something that fitted', they're not right but I can still ride until I can track down another option (thanks for the input on the Hagons, sadly I'm am shopping slightly on price as everything here has to be imported – no local stock – but I wont fit crap). The front end is the big issue. I seem to remember it was a bit soft when i got the bike ( about 8 months ago) but it's since got really stiff – is that possible?
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Old 04-08-2014, 12:15 AM   #8
Buckslip OP
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Rear shock

Rear shock set-up
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Old 04-08-2014, 12:17 AM   #9
Buckslip OP
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Front weep

Oily weep around top of shock on triple clamp thing
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Old 04-08-2014, 12:18 AM   #10
Buckslip OP
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Front shock

Thanks again for any advice/mudslinging
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Old 04-08-2014, 01:55 AM   #11
Mal S7
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Looks like it might have once been cared for Buckslip, have you got a profile pic?

As per previous posts its most likely the oil

1. Drop your fork oil and replace with low viscosity 3wt -7.5wt max!

2. Check your fork sag. If you have very little then remove the top caps and adjust whatever they have jammed in there as pre-load.

3. People will tell you that Progressive fork springs are too stiff, not in my experience or those I ride with. Not at all.

You ask could they have stiffened up since you got it? Not unless they are sticking severely (got bent?)

cheers
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Old 04-08-2014, 05:09 AM   #12
100RT
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Rear shocks are adjustable but appear to be on the softest setting. They also appear to be very short. they may be bottoming out as you ride. You need a spanner wrench to adjust them. What is the measurement from mounting bolt to bolt? Center to center.
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Old 04-08-2014, 06:53 AM   #13
ÖÖ.
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Quote:
Originally Posted by Rob Farmer View Post
Whatever you do don't buy motorworks progressive springs.
Why not?
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Old 04-08-2014, 07:03 AM   #14
Kai Ju
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The front forks look fully extended which indicates springs that are way too stiff, or somebody added some preload spacers, so be careful when you take it apart to check. You might get hit with a fork cap.
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Old 04-08-2014, 07:36 AM   #15
Biebs
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Wink Drain the fork oil first thing very simple

I would refill the front forks with ATF as a start it about 7.5 weight and the correct fluid.

Cheap and easy to get


Check for the amount of fluid to put in the forks - I am guessing they are overfilled.
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