Honda Twins banner
1 - 20 of 25 Posts

·
Registered
Joined
·
54 Posts
Discussion Starter · #1 ·
My 350 is having a bit of a shifting problem and wondering what the likely culprits may be. It shifts up fine, but when downshifting sometimes the lever won't move...it feels stuck. I have to release pressure on the shifter lever and try again and it usually does the trick. It sometimes catches me off guard going into a corner, so I'd like to fix it.
I adjusted the clutch, the lever has free play, and I lubed the cable lever pivot. I also lubed the external shift linkages/pivots. It has conventional 10/40 oil that is motorcycle specific in it. The clutch doesn't slip under load, but it is a little grabby. It doesn't engage really smoothly...as you slowly let it out, it gets to a point where it just grabs and you're off. It doesn't pop out of gear and neutral is easy to find. No problem with false neutrals, either.
Is there a shifter linkage under the rear left engine cover that could need to be cleaned/lubed? I'm hoping it isn't as involved as the shift drum or forks. If it needs a new clutch, I can handle that. This sort of has me puzzled, as it upshifts fine. Just seems like it hangs up on the downshifts. Any ideas of what it could be based on this info?
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #3 ·
I'm a bit ignorant when it comes to bikes...what are the detents? thanks
 

·
Sensei
Joined
·
27,183 Posts
Sorry... Got lost in work this week...... The detents are little spring-loaded mechanical "stops" that loosely hold the shift drum selector "star" in place to "lock" it in a particular gear......On a 350, there is a "neutral" stop bolt on the top of the cases (has a lock tab and is a fairly good size bolt head) and there is a spring and ball underneath it that "locks" it in neutral.....AND a Metal bar with a wheel on it behind the clutch... If the "axle" for that wheel, or the wheel itself is worn, the shifting will be "sticky".... Wear on the pawl (the "fingers" that grab the pins to spin the drum) or a weakened spring on the shift "arm" can also cause problems.... ALL this is behind the clutch, under the right side-case......
HOWEVER, wear or "slop" in the external linkage is just as likely the cause....Check that first ...It should move smoothly, and without binding, yet have minimal "play"(slop)..... They are most efficient if the angle of the two levers is approximately the same, and this can be adjusted or the short splined lever on the shaft moved a bit to accomplish....
Let us know what you find outside, then we'll proceed internally IF necessary....
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #6 ·
work has a way of getting in the way, doesn't it? :) thanks for the explanation.
there is lots of "slop" in the shifter linkage. I messed with the adjuster, but there really isnt a way to get that play out of the lever that I can see. the shift lever is mounted on a bushing, so it rotates freely. so expanding the shift linkage (making it longer) causes the lever to sit lower; shortening it makes it sit higher...it doesn't get rid of the slop. Maybe I misunderstood your instructions, but I messed around with it for a while and coulnd't get rid of the slop. however, the linkage moves freely and doesn't hang up or stick. I did notice that the splined shift shaft (not sure of the terminology) that sticks out of the case has about 1/8" side-to-side play. not sure if that is normal.
 

·
Sensei
Joined
·
27,183 Posts
I'm familiar with the 350 linkage, and I do not mean the "slop" on the bushing... I meant that the two short levers (on the shaft, and the short side of the foot lever) should "point" at relatively the same angle and the "ball" joints should be free to move, but "tight" (no excessive wear or slop between the linkage and arms)... You DO have to release pressure between shifts (up or down) so the pawl inside is free to "regrab" the shift drums' pins.... If you adjusted your lever (or keep your foot on the pedal) so that your foot applies constant pressure, that would be the problem... You kind of have to "step" the shifts with separate and deliberate taps of your foot, releasing pressure between each gear.... That's normal for these bikes....
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #8 ·
The shift linkage sounds worn...those pins held in place by cotter pins that hold it all together allow about an inch of play at the tip of the shift lever. Yes, I've been using the deliberate and separate movements of the shift lever...I have to "retry" the downshifts because the lever feels stuck and won't move. never been a fan of multiple shifts (skipping gears) I always like to downshift, front brake/blip, use some engine braking with the brakes, repeat. always take my foot off the shifter unless actually shifting.

A thought...If the extra play in the linkage were the problem, wouldn't I have trouble with both upshifts and downshifts...just playing devils adv. before I buy more parts for my heap! ;)
 

·
Sensei
Joined
·
27,183 Posts
What I'm trying to emphasize is that having the "short" levers approximately parallel will keep the relative movements even and smooth... A difference in angle will "favor" shifting in one direction over the other as the "push" or "pull" (whichever at the moment)will have more mechanical advantage in one direction (compared to the other).... Set the angle on the pedal to suit your comfortable foot angle... Then match the angle of the "short" lever on the pedal by adjusting the other short lever on the splined shaft..... Then adjust the rod to keep this relative positioning
otherwise, when one lever is moving directly forwards, the lever it links to may be trying to arc upwards, causing loss of mechanical force and distance, causing missed or incomplete shifts.... I can draw this better than explain it....
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #10 ·
Hmmm...looked to see what the financial damage would be for the worn parts, but they are not available from the online sources I checked. My bike has only 12k on it...hard to believe so many parts are toast after so few miles.
 

·
Sensei
Joined
·
27,183 Posts
I don't think they are "toast", I believe that properly adjusting them will cure the problem unless it's something internal (bent forks, etc...)... I'll draw what I mean and post tomorrow....
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #12 ·
ok...sorry this is taking so long to sink in...I understand what you are saying now. I'll check tomorrow to see if I have the to short levers close to parallel.
 

·
Sensei
Joined
·
27,183 Posts
Probably my explainations fault...I can picture the action of all the parts in my head and see where the conflict lies, but transferring that picture into your head with just words is often somewhat difficult for me.......
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #14 ·
Here's a shot of the shift linkage...see what you think...Does it look lined up properly?



Here are two photos showing the amount of slop or play in the shift lever:


Looks to be between 3/4 and 1"...is that too much?
 

·
Registered
Joined
·
3,926 Posts
Over the years the linkages just wear like that. It looks like to me that your front clevis is cocked to one side indicating wear on that clevis pin in the front. Although, I'm sure the wear is in both clevis' equally..

GB :mrgreen:
 

·
Sensei
Joined
·
27,183 Posts
UH...NO.... The distance from the center of the splined shaft to the center of the pedal pivot post should be equal to the distance (center to center) of the linkage rod pivots.....You want a parallelogram, not a trapezious...
Since the pedal pivot to its (short lever) pivot is offset forwards, the lever on the splined shaft would also be set the same angle forward.... However, ideally, the two short levers should be positioned "straight down" (or straight up) as this allows the LEAST amount of arc rise/fall during the shifting, meaning MOST of the force is applied at nearly 100%....

Let's try this explaination....
As it is, when you downshift, the pedal's small lever travels (arcs) both back and down....
the shafts' lever tries to go back but (arcs) upwards....
The force vectors for the total distance of travel directional difference are wasted (they don't "help" the rotation signifigantly), perhaps contributing to the "incomplete" shifts......

If we exaggerate this condition, it makes it easier to conceptualize.....,
at some point, the vector of force is pulling directly on the shaft rather than rotating it.......
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #17 ·
Back to the garage I go. Makes more and more sense, thanks, 66. I'm just glad its me and not the bike :lol:
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #18 ·
Well...I got it closer than before, but the distance between clevis pins is shorter than the distance between the splined shaft and the lever pivot. I can't get the length of the mechanism any longer...otherwise the shifter either makes contact with the pipe or the linkage binds up on itself (reaches the limit of its range of motion). That's about the best I can do with what is there. I took some time and experimented with it...different lenghs, different settings on the splines. It improved things a little, and thought I had the problem solved, but as the bike ran a bit more and heated up, the problem surfaced again. So I'm not sure if the pins/link ends need to be replaced as well (they definitely seem worn, but rotate freely), or if it is something else.
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #19 ·

·
Sensei
Joined
·
27,183 Posts
Looks like the stock CB/CL 450 shifter..... Splines are the same on the 350's, but
wether or not the footpeg would be in reach is the question......
 

Attachments

1 - 20 of 25 Posts
Top