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MarkLathrope

Beta 2006 rev 3 250

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Guys i need help with bleeding the clutch i can not get any pressure via the bleed nipple clutch end 

After changing the bleed nipple and banjo nut and copper washers, originally i just want to replace the clutch fluid after inspection it was filthy and bleed nipple rusted solid

is there a secret way of bleeding the clutch 

i ve even opened the bleed nipple tube in a bottle and left it open for a couple of hours to see it it would run through with gravity 

thanks 

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Reverse bleeding is the answer, you dont move the lever with this method. 

You’ll need a syringe, one the size of a regular tube of toothpaste. At least 3feet of clear plastic tubing. 

Ensure the bleed nipple is clear, snug it down just over finger tight, leave a ring spanner on the nipple, push the end of the clear tube onto the nipple ensure its tight and not going to let air in. Pull out the syringe plunger. Connect the other end of the clear tube to the syringe body. Cable tie or string the syringe body to the handlebar grip. With another syringe ( so you’ll need two the same size) and good quality brake fluid suck up some fluid and carefully inject it into the hanging syringe. Carefully insert the syringe plunger into its body now full of fluid, open the bleed nipple about a quarter turn and gently force the fluid into the slave cylinder nipple. This fluid will come up into the clutch master cylinder fluid reservoir, this is tiny so prepare for spillage. Thats it you now keep forcibg fluid through until no bipubbles are seen in the tube and the fluid in the reservoir is clean. Tighten the bleed nipple but not too much! 

The fluid will change colour as the seal degenerates by shedding tiny microscopic pieces of itself into the fluid.

Note brake fluid is Hygroscopic ( yes that is spelt correctly) which means the fuid absorbs moisture from the atmosphere reducing the fluids life and operating potential. In the brake system this moisture will boil before the brake fluid causing steam vapour in the brake line and long lever/pedal travel. This is a main reason for fluid changes on a regular basis.

If after all this you still have a poor feel to the clutch it may be a leaking seal allowing air in and fluid out. You also get the situation wherea seal does not leak but still allows air into the system.??Hope this helps you.

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 Nothing will bleed in either direction if there is no free play at the lever, which is usually the problem in the first place.

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8 hours ago, lineaway said:

 Nothing will bleed in either direction if there is no free play at the lever, which is usually the problem in the first place.

I was reffering to no lever movement in terms of using to pump the mastercylinder as a bleeding method.

Yes of course there should be a small amount of free play between lever and mastercylinder piston as per the manufacturer. Perhaps in hindsight I should have mentioned your point....?

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To be fair I’ve tried both ways I cannot get fluid in or out of the master cylinder now I’ve tried pushin it up with lever in and out 

and tried sucking it back through as well I’ve got most of the dirty fluid back out now  but it will not suck any clean down ether ?

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Is the master cylinder piston returning fully to the retaining circlip?It needs to otherwise fluid can't flow into it

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 Just remove the lever and pump it with a phillips screwdriver. With the lever out of the way the piston should return all the way. If that does not work, remove the clutch line from the M/C and see if you can get fluid out of the m/c.

Edited by lineaway

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On 1/16/2019 at 9:03 PM, section swept said:

Reverse bleeding is the answer, you dont move the lever with this method. 

You’ll need a syringe, one the size of a regular tube of toothpaste. At least 3feet of clear plastic tubing. 

Ensure the bleed nipple is clear, snug it down just over finger tight, leave a ring spanner on the nipple, push the end of the clear tube onto the nipple ensure its tight and not going to let air in. Pull out the syringe plunger. Connect the other end of the clear tube to the syringe body. Cable tie or string the syringe body to the handlebar grip. With another syringe ( so you’ll need two the same size) and good quality brake fluid suck up some fluid and carefully inject it into the hanging syringe. Carefully insert the syringe plunger into its body now full of fluid, open the bleed nipple about a quarter turn and gently force the fluid into the slave cylinder nipple. This fluid will come up into the clutch master cylinder fluid reservoir, this is tiny so prepare for spillage. Thats it you now keep forcibg fluid through until no bipubbles are seen in the tube and the fluid in the reservoir is clean. Tighten the bleed nipple but not too much! 

The fluid will change colour as the seal degenerates by shedding tiny microscopic pieces of itself into the fluid.

Note brake fluid is Hygroscopic ( yes that is spelt correctly) which means the fuid absorbs moisture from the atmosphere reducing the fluids life and operating potential. In the brake system this moisture will boil before the brake fluid causing steam vapour in the brake line and long lever/pedal travel. This is a main reason for fluid changes on a regular basis.

If after all this you still have a poor feel to the clutch it may be a leaking seal allowing air in and fluid out. You also get the situation wherea seal does not leak but still allows air into the system.??Hope this helps you.

Job done this morning step by step 

in the end I took the lever out pumped the master cylinder a couple of time  then took out the clutch line from the top forced the fluid back up the line in a a bottle  locked off the bleed nipple drained out the master cylinder connected back up the line and refilled the cylinder via the  syringe perfect pushed all the air up and out  ?

thank you again 

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2 hours ago, MarkLathrope said:

Job done this morning step by step 

in the end I took the lever out pumped the master cylinder a couple of time  then took out the clutch line from the top forced the fluid back up the line in a a bottle  locked off the bleed nipple drained out the master cylinder connected back up the line and refilled the cylinder via the  syringe perfect pushed all the air up and out  ?

thank you again 

Glad to be of help?

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