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So the bike had 6 yr old clutch fluid that was a milky color when I got it, clutch worked fine though (although the guy said he had just had the clutch line bleed and had the dealer's paper work to show he was charged for it).

Anyway, sucked out the milky fluid from the reservoir and then filled with new and used the clutch lever to pump through fresh DOT4, thought I was done. But here is the problem, was riding and a light turned red so I pulled in the clutch and down shifted from 6th to neutral, as I got to neutral the light turned green so I tried to up shift to 3rd with the clutch still held in, but could not, heard the gears about to clash. Had to down shift to 1st with some clashing as the gears went in, and then no more problems for the rest of the ride. Sometimes it has also been hard to get into 1st from neutral, all after the first clutch line bleed.

Thinking I have some air in there from the first bleed, do you think a vacuum brake line extractor pump will do the job right?

Based on your post it appears that you have some entrained air in the system.

When you removed the brake fluid from the masster cylinder, did you uncover the feed hole to the piston (a small hole in the floor of the MC) if so, you drew some air into the MC which it usually goes to the highest point.

You might have to bleed the MC and then the system.

Boxermania,
How do I bleed the clutch master cylinder? I know where it is, but do I have to do anything other than run enough fluid through the system to get the air in the master cylinder out the rear drain?
Thanks for the help

Look at the MC and notice that with the bike levelthe banjo fiting (where the clutch line hooks to the MC) is the highest point, where the entrained air will typically lodge.

There are two ways to get the air out, one messy and the other easy.

The messy would be by pumping the MC lever and cracking the banjo fitting, hoping that the air will bleed out. The downside is the there will be brake fluid around that wil have to be collected and wiped clean or the painted surfaces will be damaged.

The easy way is to loosen the MC from the handle bar and tip it in such a way that the reservoir is located at the highest point and pump the lever several times.....the entrained air should travel to the highest point, now the reservoir and cease to be a problem. Just make sure that the hole in the reservoir that feeds the piston is not uncovered.

Then proceed to bleed the system again, at the slave cylinder.

Make the easy shots first. Be sure there is enough DOT4 fluid in the reservoir, then do the following bleed back procedure without removing the master cylinder cover:

Sitting on the bike;
--Grab and hold the front brake until the very end of the procedure.
--Turn the bars to the right steering stop.
--Tilt the bike to the right as far as you can. Get help if you need it.
--Cycle the clutch lever in-n-out at least a dozen times. Try small squeeze-n-releases . . . . just enough to click the stop lite microswitches. That purges any master cylinder piston bore air bubbles waiting to exit up-n-out the tiny master cylinder bleedback hole.
--Then try a slow full squeeze to the grip . . . . hold it there . . . . then release it quickly. Do it several times. That moves fluid slowly passed trapped air without moving it, then the quick release knocks it out of it's cavity and upward to the reservoir.
--Repeat the small squeeze-n-releases again.

Your lever should show a big improvement. That procedure is worth doing by everyone every once-in-a-while to optimize the clutch release system.

.

Okay, will give that a try too. Just re-did the bleed procedure and the clutch feels good and had no problems in a road test down shifting up shifting. A lot of air came out the drain out

CycleRob wrote: --Then try a slow full squeeze to the grip . . . . hold it there . . . . then release it quickly. Do it several times.
.

Thanx Rob; worked for me too

CycleRob wrote:Make the easy shots first. Be sure there is enough DOT4 fluid in the reservoir, then do the following bleed back procedure without removing the master cylinder cover:

Sitting on the bike;
--Grab and hold the front brake until the very end of the procedure.
--Turn the bars to the right steering stop.
--Tilt the bike to the right as far as you can. Get help if you need it.
--Cycle the clutch lever in-n-out at least a dozen times. Try small squeeze-n-releases . . . . just enough to click the stop lite microswitches. That purges any master cylinder piston bore air bubbles waiting to exit up-n-out the tiny master cylinder bleedback hole.
--Then try a slow full squeeze to the grip . . . . hold it there . . . . then release it quickly. Do it several times. That moves fluid slowly passed trapped air without moving it, then the quick release knocks it out of it's cavity and upward to the reservoir.
--Repeat the small squeeze-n-releases again.

Your lever should show a big improvement. That procedure is worth doing by everyone every once-in-a-while to optimize the clutch release system.

.

Thanks for your help

CycleRob wrote:Make the easy shots first. Be sure there is enough DOT4 fluid in the reservoir, then do the following bleed back procedure without removing the master cylinder cover:

Sitting on the bike;
--Grab and hold the front brake until the very end of the procedure.
--Turn the bars to the right steering stop.
--Tilt the bike to the right as far as you can. Get help if you need it.
--Cycle the clutch lever in-n-out at least a dozen times. Try small squeeze-n-releases . . . . just enough to click the stop lite microswitches. That purges any master cylinder piston bore air bubbles waiting to exit up-n-out the tiny master cylinder bleedback hole.
--Then try a slow full squeeze to the grip . . . . hold it there . . . . then release it quickly. Do it several times. That moves fluid slowly passed trapped air without moving it, then the quick release knocks it out of it's cavity and upward to the reservoir.
--Repeat the small squeeze-n-releases again.

Your lever should show a big improvement. That procedure is worth doing by everyone every once-in-a-while to optimize the clutch release system.

.

Does the same procedure apply to the brake lever? I replaced that brake line during ABS servicing. Maybe I left a little air at that connection?

harveyrawn,

Yes, it applies to the brake lever too, only tilt the bike the other way. Sidestand in a slight depression for greater lean angle and full left steering lock. Of course you won't be able to squeeze the lever as much, but any air trapped up high will bubble up into the reservoir's upper airspace.

.

CycleRob wrote:harveyrawn,

Yes, it applies to the brake lever too, only tilt the bike the other way. Sidestand in a slight depression for greater lean angle and full left steering lock. Of course you won't be able to squeeze the lever as much, but any air trapped up high will bubble up into the reservoir's upper airspace.

.

Great. Thanks.