I changed my clutch with a Barnett clutch two months ago. One of my plates was worn down to nothing. Bike ran good with new clutch. Then it started getting hard to shift it up outta first when the bike was cold.
I bleed the hydraulic clutch about a month ago. Worked a little better.
Bike sat for about three weeks. Yesterday I simply couldn't get it outta first gear unless I totally yanked up on the shifter with all my might and I was worried I'd break the shifter.
Bike also creeps in first gear with the clutch pulled in.
Is it possible the hydraulic clutch got air in it and the clutch being pulled in is not full releasing the clutch. Is it clutch springs?
Don't know how to test it. We used regular DOT 3 brake fluid. Is that the problem?
Yesterday was bad news when I got on the bike.
Definitely a clutch not disengaging problem.
a) You probably require DOT 4 fluid.
b) Is the fluid level full?
c) Is the lever adjusted properly so that engagement happens fully before the lever hits the grip?
d) Air in the fluid is also a possibility.
I'd check these things, then drain, flush, and refill with the fluid recommended in your manual/on your reservoirs, and then adjust your lever if needed.
PhilB
Yes I agree it is def a clutch disengagement issue.
Its a 2002 Monster 620 with a hydraulic clutch. How do you adjust the clutch? I thought the hydraulic ones had no ajustment???
Yes I think it was DOT 3 that we used.
Going to bleed it all out and run DOT 4 if thats what its supposed to have. I feel no squishyness like I would think I'd feel from air in the lines, but even when fully pulled it the clutch is obviously still not fully disengaged. Thats why it creeps and also why I can shift up out of first.
My buddy says when it warms up it gets better (he was borrowing it)
I don't think thats the right answer. I want to fix it asap.
Bleeding the clutch can be both a pregnant dog and a pain in the ass.
Get a good sized bottle of Dot 4 or dot 5.1 (NOT dot 5) fluid. You can use Dot 3 in a pinch, but it's not recommended as it's boiling point is a good bit lower than DOT 4.
If you're prepared for the mess, you could reverse bleed it. You pump fluid in through the bleeder on the slave. This forces the fuild and any air up to the reservoir which will over flow. Messy, but you get the bubbles going the direction they want to travel, not attempting to drag them down along with the fluid.
Another trick is to bleed it per usual, and then leave the level strapped to the bar at full pull over night or longer. This opens the passage to the reservoir and can let any bubbles trapped at the top end of things make their way up and out of the line.
It's very hard to detect air in the clutch lines on feel alone. If it's on the brake side, it feels squishy vs firm. But on the clutch, it always feels squishy due to the fact you're pressing against a set of springs.
I'm not sure about your particular bike, but most Monsters have some sort of adjustment at the lever.
PhilB
Given that the issue developed over time, after the installation of the new clutch pack and was not directly associated with any changes at the master like free play adjustment it's probably nothing to do with that adjustment.
Yea I don't think its that adjustment either. When I did the clutch it was definitiely 100% dissengaged when I pulled the clutch in once I reassembled it before putting the clutch cover on and filling it full of oil.
My friend who was borrowing it says that the clutch doesn't drag after it warms up and that it shifts easier then, but it either needs to get air out of the lines or an adjustment. Its not right right now.
Will try bleeding it when I get home and get him over to help me.
Less drag after warm up is normal. Warm oil is less viscous, so less drag is the norm. And you'll always have some drag in a wet clutch. The oil does transmit a small bit of engine force from plate to plate even when the clutch is operating 100% correctly. It's not enough to make difference of the bike is on the road - but you can get the rear wheel to spin on a rear stand with the lever pulled in and the bike in gear.
But excess drag is most commonly associated with air in the line. If it didn't happen when it was cold, but when hot that's a different problem - same solution though. IN that case you have very wet fluid that's boiling out and creating steam bubbles.
If it were water boiling out the increased pressure from the steam would cause your clutch to slip, not grab. The DOT3 fluid is also not the problem but it does have a lower boiling point than DOT4.
Quote from: Slide Panda on June 27, 2012, 06:56:39 AM
Another trick is to bleed it per usual, and then leave the level strapped to the bar at full pull over night or longer. This opens the passage to the reservoir and can let any bubbles trapped at the top end of things make their way up and out of the line.
Try this ^. Also, if you are going to change out the fluid, with the reservoir about half full you should be able to see a little jet of fluid into the reservoir when you pull the lever. Tapping on the master while you squeeze the lever to get that little spurt, you may see some small bubbles of air flow back into the reservoir. Be pretty careful, the fluid can eat paint.
Quote from: Peggy on June 27, 2012, 12:25:43 PM
If it were water boiling out the increased pressure from the steam would cause your clutch to slip, not grab. The DOT3 fluid is also not the problem but it does have a lower boiling point than DOT4.
Incorrect! Steam is highly compressible - more so than air. So end up with less ability to disengage the clutch with boiled out steam in the fluid column. Remember that over pressure just backs fluid to the reservoir (to a point) and it doesn't increase the pressure in the line between the master and slave - given that the return port to the reservoir isn't blocked for some reason.
It's that return port that gets people in trouble when they install new levers - they tend to over adjust (no free play) and block the return. In brakes this will cause them to lock up as the fluid heats
It's very unlikely the clutch fluid is getting hot enough to boil water, and while the steam is compressible the system is still closed, so there would be a pressure increase. Unless I missed it, the OP hasn't said he adjusted the bleed back screw so that shouldn't be the problem, and yes, that would cause the clutch to slip. There is no harm in changing the fluid, but I don't think that's his problem.
Er water does boil at only 212 F :) and yes I know it mixes into brake fluid - it's not a suspension.
And yeah, he hasn't fussed with that adjustment.
Really just sounds to me like a good leaching... er bleeding will sort things out. Occams Razor and all...
Now we are getting somewhere maybe. When i bleed the clutch we twisted open the nipple screw down by your feet area and just kept watching as bubbles came out of it. We did the pump, open nipple, watch bubbles come out, close, pump, open watch bubbles come out routine....
Is that the bleed back screw? We did this till we saw no more bubbles. (it took forever)
Then we filled up the reservoir, screwed the lid back on and it seemed good. But then it just started getting worse over time. (the last month or so) Bike has not seen much riding in that time though.
The bleed back Peggy mentions is part of the master - don't mess unless you need to.
The bleeder attached to the clutch slave/line is where you want to be working - unless you're fortunate enough to have bleeders on the master like the 1100 or S4Rs
As noted, I think you should repeat that (PITA) bleed process, and at the end strap the lever to the bar and let sit over night. Flush out all that DOT 3 with DOT 4 or 5.1. Ensuring that the hydraulic fluid is good and air free is something that you need to do before you should be looking at any other issues. If that's not right, you'll be chasing ghosts.
If after you bleed the hell out of it the problem return in a few weeks/month then there is some other issue that needs to be tracked. Bleeding the clutch shold be a yearly thing not monthly.
Quote from: Slide Panda on June 27, 2012, 12:48:09 PM
Er water does boil at only 212 F :) and yes I know it mixes into brake fluid - it's not a suspension.
And yeah, he hasn't fussed with that adjustment.
Really just sounds to me like a good leaching... er bleeding will sort things out. Occams Razor and all...
We're arguing the same side of the argument ;D
FWIW, he's probably seeing oil temps of only 180 or so. The clutch fluid shouldn't be hotter than that.
Absolutely make sure there is fresh fluid with no air. If that doesn't solve it then we will start again. With that much air in the lines there is probably air trapped at the master. I have also removed the slave cylinder, used a clamp to hold the piston in and hung it above the master to get rid of stubborn bubbles
I really have no idea how hot clutch fluid can get in the slave, but the engine case it is mounted to can get hot enough to blister paint so I wouldn't discount that possibility. Besides, as stated before, a fluid change and bleed won't hurt. Besides, clutch and brake fluid should be changed annually anyway.
More info is needed for diagnosis. Are you using a different weight or brand of oil? Do you live in the southern hemisphere where it would be getting colder this time of year? Did you inspect the slave for seepage? It should be dry around the weep hole. Has the bike been for a good, long ride since the problem started?
Clutches can be difficult to bleed. You want to start with the reservoir as level as possible to prevent trapped air in the master. Bleed slowly, quick pumping of the lever can torn a big air bubble into a bunch of small ones, making bleeding difficult. [bang] Missed your last post. If you bleed, it gets better and in a short period of time it gets worse again and again air is getting in. You have a small leak, probably the slave.
My bike did what sounds like the same thing. It got worse over time until if I sat idling in 1st gear it would just pull off on its own. It was the master leaking. Replaced it for about $250. fixed it.
+1
If you are bleeding correctly (pick up a brake/clutch bleeding kit or vaccum pump from an autoparts store....makes this job ten times faster/easier) and the clutch is performing properly as you say after the bleed, then gets progressively worse. Air is being introduced to the system. Check your reservoir diaphargm for holes, bleeder nipple, master etc. I have seen masters with rubber diaphrgms develop a small hole/tear and actually pump air into the line the more you use it.
I've had poor results with Barnett clutches in the wet-clutch bikes.
They drag a *lot* when when the engine's cold, and still drag when the engine's hot.
Finding neutral at a stop is impossible.
I've replaced them with OEM plates, and then the problems are gone.
How many miles on the bike?