ST1100 clutch fluid - best how-to method?

Joined
Aug 21, 2018
Messages
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Location
Richmond, VA
Bike
'01 & '96 ST1100s
STOC #
9007
I'm ready to replace my clutch fluid. Is there a definitive how-to post, thread, or sticky?

I know the clutch-spring releasing trick, and understand the mechanical basics.

More like how few body pieces I need to remove, any special tools needed, etc.

I have the shop manual, but I prefer using the methods of experienced riders.
 
"I know the clutch-spring releasing trick, and understand the mechanical basics."

What's the clutch-spring releasing trick?


Last time I did the clutch, I started with a new (empty) slave cylinder and an empty master cylinder. After installing the slave cylinder, I cracked the bleeder a 1/4-1/2 turn. Positioned the handle bars so the MC was level. Filled close to the top of the reservoir. After the slave dripped a few drops I tightened the bleeder. Checked the reservoir and pumped the handle. Felt pretty good. Rigged up my bungie cord to pull the lever and laid down to proceed to bleed the slave cylinder. After a couple of the get down-get up routines I buttoned up the reservoir. Fired up the motor and checked the clutch for engagement-disengagement. Seemed good. Raised the kick stand for a test ride. Everything worked as usual. It all seemed too easy. Must have been my day!
 
What's the clutch-spring releasing trick?
You squeeze and hold the clutch lever, crack the slave cylinder nipple, and let the clutch springs force out the fluid.

Close, pump, squeeze and hold, open, close, repeat.
 
No tricks here, none needed,
Crack the nipple, let it flow nice and slow, top up when required, lock it back up, sorted.
Perhaps I was just plain lucky, but the brakes bleed just the same.
I'm blessed.
Upt'North.
 
I used a Speed Bleeder and I purchased a bag and line from them as well. You just need to know the size of the bleeder nipple. I’ve had it on there for years so bleeding my clutch is very easy, and you can focus your efforts up by the clutch MC (so as not to accidentally draw in air by letting the level of fluid go too low). I also start by using a syringe and remove the existing fluid from the MC, then refill with fresh before I begin. I can flush the fluid in under 5 minutes and generally do it with an oil change (as long as the gray lower fairing is off the bike).

EDIT: here’s a quote from a thread on ST-Owners:
‘No need to remove a bleeder to compare to the picture. Just get the SB8125Ls. The short nipple on the SB8125 can be difficult to keep a bleed hose on. I used three (125Ls) for the brakes on my '93 1100, 2 front and 1 rear, and I put a 125LL on the clutch, but in hindsight, I think a 125L would have been fine.’

In retrospect, the bleeder number SB8125L is the one for both the brakes and the clutch. Speed Bleeders sells a drainage bag and a silicone line (I’ve used this for years and it works very well). When you put the bleeder in, just unscrew the old one, have no pressure on the brake or clutch lever, and rather quickly screw in the new one (a little fluid comes out, just a little). Tighten with an 8 mm box wrench so you don’t apply too much force to the bleeder. Just snug it up is all, then do the bleed procedure (after loosening the bleeder about 1/8 turn). Piece of cake actually, and I always found this job daunting (until I actually did it for the first time) and realized how easy it is.
 
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I used a Speed Bleeder and I purchased a bag and line from them as well.

I did this as well, Speed Bleeders work well for clutch and brake bleeding. People say you don't need them but I wonder how a single person bleeds the left front caliper, pretty awkward and time consuming IMO.
 
....Remember to cover the false tank - 'cos you're going to bump your head on the handlebars and splash some juice about - and it's a damned good paint stripper..... :thumb:
Great caution!!! I cover the area with a trash bag, over the front of the tank and over the fairing/pockets where fluid may splash...then cover that with an old shop towel.
 
In retrospect, the bleeder number SB8125L is the one for both the brakes and the clutch.
So, the Speed Bleeder is just a replacement bleeder nipple? You just leave it open during bleeding, and leave it on the bike after?

Is there a how-to post or thread? I don't see a clutch section in the ST1100 Tech sections.
 
So, the Speed Bleeder is just a replacement bleeder nipple? You just leave it open during bleeding, and leave it on the bike after?

Is there a how-to post or thread? I don't see a clutch section in the ST1100 Tech sections.
Exactly…it’s a replacement bleeder with a ball valve and spring, so you can pump away at the lever and watch the MC fluid level drop, refill and don’t worry about down below til you’re done. Unscrew old bleeder, lose a marginal amount of fluid, replace with Speed Bleeder (tighten fully), and go to work. Open 1/8 turn, pump old fluid out, watch fluid level in MC so it doesn’t draw air, keep going til you’re satisfied with clean fluid coming out at the nipple, then close the nipple by 1/8 turn, close up the MC cap, and you’re done (10 minutes tops). I also like the bag with the silicone line as it stays well on the nipple, so there’s no spillage of the brake fluid. The bag and silicone line are reusable, just put the line into a bottle and invert the bag so the old, used brake fluid can be stored in the bottle (like soda bottle) for recycling.

I even put one on the clutch slave cylinder of my MR2, so that’s a one man job as long as you’re watching the MC fluid level carefully when pumping the clutch pedal.

This video shows the install procedure very well:

For the brakes on my cars, even though I don’t have speed bleeders on them, I have a special bottle with some fluid in the base and can bleed all 4 wheels in about an hour per car (have to put the wheels up on ramps to do this though). It’s one of those jobs that is conceptually difficult, until you do it, then realize why did you pay someone to do it all this time (although garages will typically use a vacuum tool or electric pump to pull the fluid through vs pushing it out).
 
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It has a socket with a rubber boot in it that fits over the existing nipple and has a check valve incorporated as well. My clutch and rear brake are 10 mm but the front brake calipers are 8 mm
speed bleeder.PNG
 
I’ve seen that one from Motion Pro…looks like a good option as well. I believe with the speed bleeders, all of the nipples for the ST become 8 mm size (from 10 mm at the specific OEM nipples) so just one box wrench is used for all.
 
I didn't have good luck with the Tool pictured above, it didn't seal that well and only fit one (8 or 10mm) of my bleeders.
Better option is the Motion pro inline bleeder tool.
 
Better option is the Motion pro inline bleeder tool.
The design with the built-in wrench also limits its use in tight spaces. I prefer the in-line as well.
 
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I didn't have good luck with the Tool pictured above, it didn't seal that well and only fit one (8 or 10mm) of my bleeders.
Better option is the Motion pro inline bleeder tool.
yes it is a bit fiddley to seat correctly in tight spaces, but works fine. I have both 8 & 10 mm ones.
 
I didn't have good luck with the Tool pictured above, it didn't seal that well and only fit one (8 or 10mm) of my bleeders.
Better option is the Motion pro inline bleeder tool.
Add me to the list… I have both sizes of the newer Motion Pro and they both failed. Get the old in-line version. Tried and true! JMHO

John
 
Okay, now I'm really ready to do it. I have fresh DOT4 and what else I need.

Which body panels must be removed and what tools are needed to remove them?
 
Allen key to remove the fasteners. (One odd one throttle side last one in the line.) Pull the two rivets loose inside the front. Wiggle and fiddle the grey plastic loose. JIS screwdriver to remove the master cylinder cover - remove the plastic and rubber thingies and put somewhere clean and safe. Can you syringe most of the old juice out? Don't loosen the slave nipple much - that is
barely enough to pass fluid with resistance. It won't suck air back. Pump until clean comes out. Don't overtighten the nipple after...... If air gets sucked in the top, just fidget with the lever and it will bubble back out....
 
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