Popping INTO gear???

Joined
Jun 14, 2007
Messages
1,736
Country flag
I've heard people talk about Commandos that will pop out of gear - a symption of the dread Layshaft Bearing Disease, among other possible cause? - but mine pops INTO gear on occasion if I put it in neutral, am coasting to a stop, and apply the brakes. Not always, but once in a while. Anybody heard of/familiar with this? Is it a symptom of another problem?

Thanks - BrianK
 
Joined
Mar 6, 2007
Messages
87
Brian
I had this with mine a wee while ago. Just as you describe it. mine also came out of 1st while pulling away. It turned out to be the neutral switch was scewed in too far and puting too much pressure on the camplate.
The neutral switch plunger left a groove on the dimple which operates it.
After Norman White diagnosed it I backed off the switch and the problem's solved.

millard
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
17,998
Country flag
Brian

When this happens does it normally drop back into the gear you were in (if you selected neutral from first does it drop back into first) or go into second etc.?
 
Joined
Jul 18, 2004
Messages
327
I know exactly what you mean. I get the same false neutral that pops into first just as I am about to stop. I guess I have overshot neutral by a bit. With light touch and a careful foot I can avoid it. The box is fine otherwise, I renewed the bushes, replaced three gears etc...

I also notice that sometimes I have to back off he throttle and let the revs die down to get into 4th if I have been really gunning it. The lever does not catch the gear.

I realize this isn't the smooth as silk gearbox off my Honda!8) I am assuming these are quirks of a gearbox designed in 1936 - if they are indicative of something wrong, let me know!
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,111
Country flag
First off, check the thin hairpin spring in the outer gearbox cover. This is prone to rust as it is out of the oil bath and it tends to lose its tension. When this happens the shift selector pawl does not catch the proper detent (if at all).

Second, I have found that false neutrals and popping into gear are exaggerated by an improperly adjusted clutch and/or notched clutch hub or a too tight primary chain. If the clutch drags, it not only is difficult to find neutral, but it doesn't allow the gear to move into the proper position.

The too tight primary chain, because of the long unsupported length of the shaft and heavy clutch assembly can actually put enough pressure on the mainshaft fourth gear to generate enough friction in the bushing to turn the gear. If you put the bike on the centerstand and the rear wheel turns in neutral while idling, your primary chain is too tight.
 
Joined
Jun 14, 2007
Messages
1,736
Country flag
My rear wheel does spin when on centerstand in neutral with motor running, but I just checked the primary chain tension and it seems right (perhaps a bit LOOSE if anything). What else would cause that? Thanks - BrianK
 
Joined
Apr 7, 2004
Messages
1,691
Clutch plate drag is almost always the root cause. If you haven't pulled the plates and cleaned them checked for burs than the process of tracing the fault gets much more difficult. When you do this job have a paint marker on the ready. All the steels and frictions should go back in just the way they came out. Don't mix them up and keep the splines in order if you don't the process of re-bedding the spines will cost you just a bit of life on the parts. You will need to mark one spline on the basket and one on the center hub, than as each plate is removed dot the end of the tab that was in the marked spline that corresponds inside out side and so on re-stacking them in order. Having the mark out on the end of the tabs prevents loosing them during the cleaning if some care is used. Good time to check the clutch rod lube and condition as well.
 
Joined
Feb 22, 2006
Messages
200
I found that at times, not all the time, mine would jump into gear as I turned the ignition off, and the rear wheel used to spin while on the stand, as Norbsa said, this seemed to be the result of clutch drag, as once the plates were cleaned up the problem disappeared.

Mike.
 
Joined
Jul 18, 2004
Messages
327
I guess it is time to check my clutch plates and primary tension! I was putting it off but I guess now is as good a time as any.:wink:

Thanks.

Phil
 
Joined
Mar 19, 2005
Messages
696
Ron L said:
The too tight primary chain, because of the long unsupported length of the shaft and heavy clutch assembly can actually put enough pressure on the main shaft fourth gear to generate enough friction in the bushing to turn the gear. If you put the bike on the centerstand and the rear wheel turns in neutral while idling, your primary chain is too tight.

Mine has always turned the wheel on the stand...if you make the chain looser, this will make for a real sloppy shifter, though, that unpleasant forward and back lag between gears. I have never had any problem with the tranny, or bearings other than that my 2nd gear has gone to pot periodically and makes a howl and metal filings in the oil. Got a magnetic drain plug for that, as I can't afford to replace gears every couple years, but that is an other subject, or?
I'd just assumed that some kind of hydrallic, turbine effect of the thick oil was pushing the gears to turn and the wheel along with it, and I am understandablely a bit hesitant to just go in and change the adjust I have had for 120 thousand miles...can you elaborate a bit as to why I should?
 
Joined
Mar 6, 2007
Messages
87
The too tight primary chain, because of the long unsupported length of the shaft and heavy clutch assembly can actually put enough pressure on the mainshaft fourth gear to generate enough friction in the bushing to turn the gear. If you put the bike on the centerstand and the rear wheel turns in neutral while idling, your primary chain is too tight.

My ES2 turns it's back wheel at quite a speed on tickover but I run the primary quite loose. I was told it was caused by "stiction" whatever that is.


millard
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,111
Country flag
My comment about the tight primary chain made the assumption that any clutch and clutch adjustment issues had been addressed first. I have three regularly ridden Commando's and none of them turn the rear wheel at idle in neutral. No primary chain slap either!
 
Joined
Mar 19, 2005
Messages
696
Ron...
Indeed fortunate, or you know what you are doing. What, though, has a clutch, or it's adjustment to do with a turning rear wheel, a bad adjustment might cause either troubles getting the gears in and out, or in the case of putting the double wammie on the clutch rod adjust, cause it to slip, but fail to see what that would have to do with anything other than those issues. The (main?) shaft in the tranny will always be turning when the motor is running because it is connected to the clutch center and the problem must be somehow connected to that fact, but the clutch or adjust, should have no effect on it...or? Enlighten me... :shock:
 

Ron L

VIP MEMBER
Joined
Feb 27, 2004
Messages
3,111
Country flag
Ya know Hewho.. as I think about it, you are right. The clutch has nothing to do with the rear wheel turning in neutral. That is dependent solely on the drag of the spinning input shaft on the sleeve gear.

The point I was initially trying to make is that a too tight primary chain will actually pull the input shaft forward enough to cause enough drag on the sleeve gear to turn the rear wheel. This will also turn the layshaft and could cause difficulty in meshing or unmeshing the gears.
 
Joined
Apr 7, 2004
Messages
1,691
The one weakness of gear lube is the difficulty it has trying to get into this area. When you look at the designs of people who have started from scratch making new components you will see this area improved. All the power going in and coming out puts a load on here.
 
Top