Partial Clutch Engagement After New Clutch Install

[Imgnr]

I just finished my first clutch job ever.  New clutch pack and new slave.

 

In first gear and with the clutch pulled in, the bike wants to move forward at about 3mph.  I have to pull in the brake to prevent it from moving.

 

Is this normal after a new clutch is installed?  Will it stop after the parts have had a chance to wear in?

 

Thank you!

[dirtrider]

19 minutes ago, Imgnr said:

I just finished my first clutch job ever.  New clutch pack and new slave.

 

In first gear and with the clutch pulled in, the bike wants to move forward at about 3mph.  I have to pull in the brake to prevent it from moving.

 

Is this normal after a new clutch is installed?  Will it stop after the parts have had a chance to wear in?

 

Thank you!

 

Evening Imgnr

 

It might get better & might not, depends on WHY it is dragging.

 

With a new slave are you SURE that you got all the air out of clutch hydraulics?

 

About all you can do is be sure that you have all the air out of the clutch hydraulics, set the clutch lever to provide max lever travel, then ride the bike. If it gets better then you are OK, if it doesn't get better then you will have to either live with it or go back in & try to find the issue.

 

 

 

 

[Lowndes]

deleted

[Imgnr]

Good news...fixed the clutch problem by bleeding the clutch again.  I didn't know that air bubbles can cause a clutch to engage.  Hopefully someone else will read this post and find it helpful.

 

Bad news...once in a while (every 6 miles or so of city riding) I cannot shift up from 2nd to 3rd gear.  It just refuses to budge.  Not sound of gears grinding, no clunk, just won't go up.  If I downshift, then I can shift up.  I saw some other post where DR said to clean the linkage.  I've done that.  I don't know if it matters, but I did use the BMW alignment tool when installing the clutch so it should be aligned.

Any other possible causes?  Before replacing the clutch, it worked fine.

[Lowndes]

Try bleeding it one more.

 

Dirt Rider will know exactly what's going on and how to fix it.

[dirtrider]

7 hours ago, Imgnr said:

Good news...fixed the clutch problem by bleeding the clutch again.  I didn't know that air bubbles can cause a clutch to engage.  Hopefully someone else will read this post and find it helpful.

 

Bad news...once in a while (every 6 miles or so of city riding) I cannot shift up from 2nd to 3rd gear.  It just refuses to budge.  Not sound of gears grinding, no clunk, just won't go up.  If I downshift, then I can shift up.  I saw some other post where DR said to clean the linkage.  I've done that.  I don't know if it matters, but I did use the BMW alignment tool when installing the clutch so it should be aligned.

Any other possible causes?  Before replacing the clutch, it worked fine.

 

Morning  Imgnr

 

A couple of possibilities, the USUAL problem with the shifter going dead & not upshifting is something sticking in the shift linkage or in the shift lever travel preventing the shift drum at the ratchet arm from fully advancing then the arm not picking up the next gear position.

 

Make darn sure that nothing is sticking or contacting/restricting the FULL articulation of the shift lever or linkage (even look at the bolt going through the short shift arm on the side of the trans to make sure it isn't hitting the trans case then make sure that the short arm is clocked correctly on the spline shaft).

 

If all is OK with the externals (Look VERY VERY VERY CLOSELY at every place it can hang up or contact something at full travel.

 

The  next place to consider is the trans internal shift drum area  (BMW had a service bulletin on a number of miss-built shift drums causing a similar problem but I'm pretty sure that was only on the 1100 bikes). 

 

If your trans neutral/gear position switch is dragging that might cause the shift drum to not spin freely enough to allow the drum lever/pawl to pick up the next gear position.

 

You need to 100% clear the externals, if no issue there then look for a neutral switch/gear position switch problem, then as a last resort look internally at the shift drum & ratchet pawl area.  

 

I might be able to tell you a little more if you can  explain EXACTLY & in DETAIL how the shift lever moves & feels when it won't advance the shift.  

[Imgnr]

I looked very closely and couldn't see where the linkages could bind but I probably don't know exactly what I'm looking for.

 

It seems to only get stuck on the 2 - 3 year up shift.  When it does happen, I downshift (keeping the clutch pulled in so the engine doesn't engage and redline the motor) to first gear then upshift twice to third. 

 

Hopefully this is a clue?

[dirtrider]

9 hours ago, Imgnr said:

I looked very closely and couldn't see where the linkages could bind but I probably don't know exactly what I'm looking for.

 

It seems to only get stuck on the 2 - 3 year up shift.  When it does happen, I downshift (keeping the clutch pulled in so the engine doesn't engage and redline the motor) to first gear then upshift twice to third. 

 

Hopefully this is a clue?

 

Morning  Imgnr

 

Yes, it's a clue but isn't definitive.

 

That does more point to an internal trans problem but doesn't eliminate an external problem.

 

It does point more away from a shift linkage problem (unless you have something limiting shift lever travel & 3rd gear takes just a bit more lever movement to engage) but still could be something like a gear indicator switch hanging up going into the 3rd gear position.

 

What happens if you shift to 2nd THEN back off the throttle a little in 2nd before de-clutching then making the shift to 3rd.

[Imgnr]

Hope I’m not celebrating too early but Lowndes wins the cake with the bleeding. 

 

During this project, I replaced the clutch line and the slave cylinder so o had to evacuate a lot of air and there’s a lot of nooks and crannies for air bubbles to hide. I have a speed nipple installed and bled the line multiple times.  

 

As a last ditch effort, I zip tied the clutch lever and left it overnight. Before releasing it, I loosened the speed bleeding screw and saw that some air seemed to come out before the fluid started to flow. I should’ve put a hose on it and the end in a small cup w brake fluid so I’ll know for certain. There is also the possibility that some bubbles came out the master cylinder as well. 

 

The shifts were much smoother and less clunky on the ride to work and there were no stuck gears. I’ll need to take a nice long ride and let the bike heat up before I can declare this a success. 

 

Hope everything is in order for a trip I’m making in early October to Mammoth Lakes and over the pass into Yosemite. 

[wbw6cos]

You could also lightly tap the lever, repeatedly,  to see if any bubbles are in the fitting near the reservoir.  Glad you sorted it out.  Lowndes is a bit of alright!

[dirtrider]

5 hours ago, Imgnr said:

Hope I’m not celebrating too early but Lowndes wins the cake with the bleeding. 

 

During this project, I replaced the clutch line and the slave cylinder so o had to evacuate a lot of air and there’s a lot of nooks and crannies for air bubbles to hide. I have a speed nipple installed and bled the line multiple times.  

 

As a last ditch effort, I zip tied the clutch lever and left it overnight. Before releasing it, I loosened the speed bleeding screw and saw that some air seemed to come out before the fluid started to flow. I should’ve put a hose on it and the end in a small cup w brake fluid so I’ll know for certain. There is also the possibility that some bubbles came out the master cylinder as well. 

 

The shifts were much smoother and less clunky on the ride to work and there were no stuck gears. I’ll need to take a nice long ride and let the bike heat up before I can declare this a success. 

 

Hope everything is in order for a trip I’m making in early October to Mammoth Lakes and over the pass into Yosemite. 

 

Evening  Imgnr

 

I hope that fixes it for you but I do have some doubts. If it was just an air issue the why only a 3rd gear problem (same clutch release for every shift). As a rule clutch hydraulics with air in it gives the most problems getting the trans into of out of neutral.

 

You also mentioned above --  "It seems to only get stuck on the 2 - 3 year up shift.  When it does happen, I downshift (keeping the clutch pulled in so the engine doesn't engage and redline the motor) to first gear then upshift twice to third" -- If you kept the clutch held in there is no change in clutch position for the second 2-3 upshift try. 

 

The only air that you really need to worry about is in the slave cylinder & lower part of the clutch line. Once the clutch line starts uphill  towards the master cylinder anything in that section & above (including the master cylinder) will self bleed back into the master cylinder due to the  amount of fluid moved in & out at each clutch lever stroke. (air rises on the fluid so will travel right up  into the master cylinder reservoir with a few clutch lever strokes) 

[Lowndes]

Well thanks guys but I'll ALWAYS DEFER to The Oracle; Dirtrider.  I probably read that suggestion somewhere in one of Dirtrider's innumerable posts. He has more experience (and sense) than all the rest of us put together, not to mention his altruistic devotion to this site and "sport".  He only has about 10,000 times more experience that I and any three other idiots do, probably more.   And, he is so humble and generous with his monumental storehouse of knowledge and notes.

 

I just see "bleeding" any system as not exactly straightforward.  "Bubbles" seem to get stuck, possibly in banjo fittings and even straight runs of tubing.  You cannot see what's going on so who knows. I know it doesn't always work like we think it's supposed to.  Bumps, knocks, vibrations, tilts, routines, alternatives, incantations, shamans, procedures, bungies, rubber hammers, speed bleeders, long rides, beer, and mity-vacs are all viable bleeder tools in my kit.

 

 

[dirtrider]

6 minutes ago, Lowndes said:

Well thanks guys but I'll ALWAYS DEFER to The Oracle; Dirtrider.  I probably read that suggestion somewhere in one of Dirtrider's innumerable posts. He has more experience (and sense) than all the rest of us put together, not to mention his altruistic devotion to this site and "sport".  He only has about 10,000 times more experience that I and any three other idiots do, probably more.   And, he is so humble and generous with his monumental storehouse of knowledge and notes.

 

I just see "bleeding" any system as not exactly straightforward.  "Bubbles" seem to get stuck, possibly in banjo fittings and even straight runs of tubing.  You cannot see what's going on so who knows. I know it doesn't always work like we think it's supposed to.  Bumps, knocks, vibrations, tilts, routines, alternatives, incantations, shamans, procedures, bungies, rubber hammers, speed bleeders, long rides, beer, and mity-vacs are all viable bleeder tools in my kit.

 

 

 

 

Evening Lowndes

 

Yes, that can be a problem on the braking hydraulics as very little fluid is moved when applying the brakes. On the clutch side much more fluid is passed in & out of the master cylinder (full stroke worth of fluid)  with each shift & launch.

 

Air can still get trapped in the clutch slave cylinder & lower horizontal line including the slave bleed line but once the clutch line starts uphill sharply the air travels right up on the fluid to the master cylinder then is quickly worked back into the master cylinder reservoir with each full  length clutch stroke.

 

 

[Lowndes]

Good morning, Dirtrider,

 

Agreed.  The Clutch system is higher volume/less pressure where the brake system is lower volume/higher pressure. 

 

Also, the small ID of the steel lines seriously slows the progress of the bubbles.  Also, pumping from the top (handlebars) trying to push the bubbles DOWN can be a stalemate.  Just watching the bubbles slowly move up thru a clear bleeder tube where the ID of the clear tube is much larger than the steel tube tells me another essential tool for bleeding (that I forgot to mention) is PATIENCE and I have to borrow that.  Sometimes I just have to let it sit overnight. 

 

 It's also important to tilt the bike (side stand) and turn the handlebars to make sure the lines and fittings are all sloped UP as steep as possible.  Banjos just by their design are air traps that take a high velocity shot of fluid to flush the small bubbles.  The process can be extremely frustrating at times.