QuestionChris-
I know that you've addressed this type of issue recently in other posts, but our particular problem is a little different. I'm really hoping you can help my husband out before he loses what little sanity I've left him with... We recently picked up a 1984 Honda Shadow, in decent condition, as a spare ride for my husband and something for me to learn on. His "real" ride is a 1959 HD XL in a hard tail chopper frame, so you know I'm not learning on that! Anyway, the Honda is having a weird problem with the clutch, and I can't find any tech boards that address the issue. When we got the bike we kept having trouble with the clutch being "soft". He got both master & slave cylinder rebuild kits and put them to work. Put everything back on the bike, bled the system ~~ still problems. Found a few postings that said to bleed the banjo bolt (after he had figured that out himself), and it seemed much better. Started the bike, ran it for about 30 minutes while I practiced circles in the parking lot, and all of a sudden the clutch was soft again! OK, so we figure there's got to be a bubble SOMEWHERE that we haven't found. The clutch line snakes in & out and up & down through the frame, so there's lots of high points for a bubble to hide. Bought a hand held vacuum bleeder from the local auto store, and at the same time upgraded from DOT 3 to DOT 4 fluid. We drained all the old (two days old!) fluid out of the system, and sucked new DOT 4 in. WOW! Clutch feels great - up the road, into the parking lot, and after 40 minutes I'm up to figure 8's. Come home, hubby takes both the kids for short rides, and by the time he's done the clutch is soft again. Now here's where it gets weird ~~ he's so frustrated that he just puts the bike up for a while. Goes back a few hours later when the bike's "Cold", and the clutch is fine again! It only seems to go soft when the system is warmed up, and we can't figure out why. He REALLY doesn't think there are any other bubbles in the line, and he's good mechanically so I believe him. Is there a different type of fluid we should use maybe? Or does any of this info trigger another idea that we should check? Please, please, any help you can give us would be so appreciated! I've only learned start and stop ~~ I want to learn how to get into 2nd gear!
Thanks!
AnswerHi Anne-Marie.
The clutch line SHOULD be a relatively straight line without any ups and downs, between the master and slave cylinders, for air to get trapped in. Check the repair manual for the details on the length of the clutch line and routing. You may have one that is a little too long, particularly if the previous owner put shorter handlebars on without changing the lines or if they have been routed improperly. That is the first thing.
Another thing to check visually is the line itself while the clutch is being engaged and disengaged. You would be looking for ballooning of the line as well as areas where it may be getting pinched or slowly leaking. Perhaps changing to a braided stainless hydraulic line is in order. Braided stainless will not expand at all and provides the best clutch pressure.
Changing to DOT4 from DOT3 may not have been a good idea. It is not normally recommended for hydraulic systems on the older Hondas. It can cause problems with the seals.
Start with those and Let me know what you find.
Good luck and ride safe.
FALCON
