gearbox 2nd-neutral-1st

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seattle##gs

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A friend has a gearbox (Commando) which gives him problems. There is no feel when it shifts into 2nd and 1st gives him false neutrals. We went through the gb and replaced all bushings and gaskets and bearings. My first thought is the detent plunger is worn or the spring needs replacing. Or, the plunger housing has a washer under it where it's supposed to fit flat to the gb with no copper or alu washer. I have heard there are two different tips on these plungers, one is very rounded and the other is pointy. However I might be confusing this with triumph. It's also possible that the camplate is worn or worse yet, both the camplate and plunger are worn a tiny amount but enough that it skips over the detent stop instead of a positive "snick". I remember looking at these parts and there was little or no wear...that I could see.
Any other ideas?
 
Maybe his camplate and quadrant timing is off. It was on mine. Something to check.
 
It makes all 4 gears up and down. The lack of feel shifting from 2nd to neutral is his concern
 
Perhaps he has a shift Fork that's slightly bent? With the shift forks and the shift shaft removed insert the shift shaft in one of the forks and use a Machinist Square to check to make sure it isn't bent
 
Oddly enough I have never encountered a bent shifting fork so I do not know the symptoms. This box shifts very well. My guess is that the camplate and plunger looked good on inspection but in use the 1st-neutral-2nd region, which gets 90% of the use, is a little less positive. However, I COULD BE WRONG. If there are any other possibilities please let me know before I go all the way in and replace a camplate. The first step (easiest) is to replace the plunger and spring for a cost of about $20.
 
seattle##gs said:
Oddly enough I have never encountered a bent shifting fork so I do not know the symptoms. This box shifts very well. My guess is that the camplate and plunger looked good on inspection but in use the 1st-neutral-2nd region, which gets 90% of the use, is a little less positive. However, I COULD BE WRONG. If there are any other possibilities please let me know before I go all the way in and replace a camplate. The first step (easiest) is to replace the plunger and spring for a cost of about $20.
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Yes. Replace the plunger and spring first.
Also you will have to remove the outer cover to fit a NEW hairspring shifter spring the correct way up if this does not correct the problem.
A sticky clutch is likely the real issue. Check mainshaft circlip for crushing and mainshaft nut is tight .
 
Torontonian said:
Also you will have to remove the outer cover to fit a NEW hairspring shifter spring the correct way up if this does not correct the problem.
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The dog-leg of the hair pin spring goes down. The spring, probably, will need bending such that there is .010 to .015 clearance between it and the pawl. I have yet to see one come out of the bag and fit properly. I could be wrong about the clearance so check a few sources, more knowledgeable members will step up.

Best.
 
If the plunger is sticking in it's tube, it won't return quick enough to locate the notch on the outside of the cam plate. a grain of metal or dirt can cause this, if it causes drag on the plunger. Just unscrew the plunger nut and check that the plunger is free to move up and down without sticking. Also the plunger's spring might be weak.
 
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I'll say it even though it may be way off base.

Primary chain or belt too tight makes shifting goofy. As mentioned, a clutch that drags will reduce "feel" at the foot lever. Mine does not snick into neutral. It kind of falls into neutral with just the right amount of pressure from my foot to get over the cam hump. Under normal circumstances I never miss neutral or any gear when the chains (both primary and drive) are properly adjusted, and the clutch is in good shape. When my primary is too tight 3rd gear is a problem sometimes. I do use the get into neutral before final stop method, unless it is a panic stop in 3rd. Then finding neutral may be challenging without some rocking and clutch shenanigans.
 
Since it is only $20 I will replace the spring and plunger just to remove it from the list of possibilities. I will double check the chain and dragging though the diaphragm clutch greatly reduces the dragging problem over the three spring clutch. All the plates are new as is the basket and center. Thanks will let you know in a couple of weeks
 
Schwany said:
Under normal circumstances I never miss neutral or any gear when the chains (both primary and drive) are properly adjusted, and the clutch is in good shape.
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I agree and would like to add that making a shift should be a deliberate action, full throw up or down with purpose, however, not a monster-mash either up or down.

Do this someplace were traffic is light until the action becomes hard-wired.

From what you have written it sounds like you know the g/b.

Best.
 
forgot to mention this is an RGM belt drive. Plenty of slack in the belt when I saw it last.
 
seattle##gs said:
Since it is only $20 I will replace the spring and plunger just to remove it from the list of possibilities. I will double check the chain and dragging though the diaphragm clutch greatly reduces the dragging problem over the three spring clutch. All the plates are new as is the basket and center. Thanks will let you know in a couple of weeks
Click to expand...
I wouldn't do just the plunger and spring. I would do the plunger and housing and optionally the spring if I were suspicious of the plunger. That said, I would think more about the clutch.

I know they are nothing alike, but most Triumph Tridents are very hard to find neutral due to the clutch not lifting enough - bike rides fine but neutral is a bear. Get the clutch to lift (separate) a few more thousandths and neutral is easy.
 
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