Trouble Shifting Into First

Hey Guys,

I have a difficult time shifting into 1st gear from neutral. At stop lights I hold the clutch in so i don't get stuck in neutral, holding up traffic, which is very frustrating in traffic and in-town riding.

Finding neutral is no problem, shifting back into 1st from 2nd is smooth and all other positions are fine. No slipping or dragging. Once in neutral (at a stand still) I have to rock the bike a bit and or shift back and forth from neutral to 1st or 2nd to 1st for it to engage.

This is consistent on both my commando's so I'm confident I have something set-up incorrectly. Both have Barnett clutch plates. I have dismantled and reassembled the clutch multiple times with no resolution to this.

any ideas?

There is two things I can think of:

1) when the gear box is rebuilt, the first gear has to be timed in a certain position ( the manual is reasonably clear on this ),

2) the plunger need to be set correct, correct spring etc etc ( the plunger pops into a different slot for each gear and neutral ).

This picture is of the cam plate in second gear ( big recess is a gear, the little recess is neutral ).

Well assuming your clutch is not dragging? It could be the area Josh showed in the picture, if the bell crank is sightly out it can foul on the casing. Does the bike hold in first gear okay, I mean if you accelerate and back off, does it neutralise? That is typically the bush on first gear layshaft.

If the clutch is the issue, search on setting up the clutch plate stack height to get the diaphragm in the sweet spot.

Cheers Richard

jsouthard said:

I have a difficult time shifting into 1st gear from neutral. At stop lights I hold the clutch in so i don't get stuck in neutral, holding up traffic, which is very frustrating in traffic and in-town riding.

Finding neutral is no problem, shifting back into 1st from 2nd is smooth and all other positions are fine. No slipping or dragging. Once in neutral (at a stand still) I have to rock the bike a bit and or shift back and forth from neutral to 1st or 2nd to 1st for it to engage.

This is consistent on both my commando's so I'm confident I have something set-up incorrectly. Both have Barnett clutch plates. I have dismantled and reassembled the clutch multiple times with no resolution to this.

Click to expand...

First question would be whether work has been done on your bikes' gearboxes? You mention that this problem occurs with both your commandos and that you've done clutch work but fail to mention whether the gearboxes have been worked on. I ask because if your clutch exhibits no slippage or dragging symptoms and is working well in all shifts except neutral to first, then your problem almost certainly is gearbox related.

stockie2 said:

Well assuming your clutch is not dragging? It could be the area Josh showed in the picture, if the bell crank is sightly out it can foul on the casing. Does the bike hold in first gear okay, I mean if you accelerate and back off, does it neutralise? That is typically the bush on first gear layshaft.

Click to expand...

Stockie2 asks the second question - once in first does it stay in first under hard acceleration? If the first,lay bush is bad it can lead to jumping out of gear or if the engagement of the second,lay dogs to first,lay is incomplete because of quadrant/camplate misalignment or camplate/shift fork/gear wear, it could do the same thing.
Just some thoughts: If it doesn't jump out of first, ever, and you can get first every time by going directly from second to first, and the quadrant/camplate setup is correct, then my guess would be play/wear somewhere which is overcome by the longer "throw" from second but causes an incomplete engagement of second,lay to first,lay when going only from neutral. Do you hear any noises when it doesn't engage normally? Does it ever seem to engage and then "jump out" of engagement when you let out the clutch? Can you find first from neutral with the bike on the center stand so you can move the rear wheel with the engine off? (should be able to go through all the gears this way without touching the clutch)

Andy has it mostly covered. First cog paper thin bush is the 1st to go in AMC boxes and its main symptom is coming out of first when power and drag become equal while going rather slow coating, not difficulty engaging. If shifts at all through the gears then the rack/pinion cam plate is properly indexed as can only work when spot on.
Reluctance to engage 1st from N could be d/t:
1. the outer cover clothes pin pawl spring is distorted right out the box or by rust and time.
2. other cog bushes are worn so shaft wobble enough not to allow alignment
3. primary chain tension is too tight once warmed
4. the shifter dogs faces are worn down, usually d/t the above putting abnormal alignment loads on them
5. greasy grimed friction plates from tranny or primary oil
6. the nut on the end of the RH side of the main shaft has backed off so clutch cable can't release the pressure on plates enough as the main shaft shifts side to side too much, a silly mm or so is all it takes.

Thanks for the suggestions and advice.

She stays in first, never jumping out. No work has been done on the '74 gearbox but the '69 was rebuilt in the last year. I was hoping it would be a quick and easy move. I will pull the gear box apart on the '74 and make sure nothing is worn or out of sync.

Thanks.

jsouthard said:

Thanks for the suggestions and advice.

She stays in first, never jumping out. No work has been done on the '74 gearbox but the '69 was rebuilt in the last year. I was hoping it would be a quick and easy move. I will pull the gear box apart on the '74 and make sure nothing is worn or out of sync.

Thanks.

Click to expand...

All work can be done with the gearbox in the cradle. It would be nice to get it up to a workable height though. Primary will have to come off. I have done work both ways. With the gearbox out, I drilled a big hole in my bench to take the main shaft/sleeve.

I feel the anyone who has worked on these just a couple of times has mastered it. I swear, once you have done it, you can't wait to do it again. :lol: Well....almost.

pvisseriii said:

All work can be done with the gearbox in the cradle. It would be nice to get it up to a workable height though. Primary will have to come off.

Click to expand...

+1 - not a hard job to do with the box in the frame. However it should be pointed out that you can essentially completely disassemble the thing, except for the mainshaft and sleeve gear, so if you find a problem by that point (almost a certainty) then the whole job can be done without removing the primary. Makes a nicer job to pull the clutch for sure, and if you want to redo the entire box and get at the 4th,main and its seal and bearing and the countershaft sprocket, then the clutch has got to come apart.
You can do the layshaft bearing at the same time, in situ and also without getting into the clutch.

However, unless I misunderstood you, I'm still really puzzled about your saying that BOTH bikes exhibited the same symptoms. One gearbox redone and one original, what are the odds?

I can't offer any advice beyond what others have posted.
However I have the same symptoms you have.
Gearbox works fine in all ways except when I shift down from second to neutral at a stop, which is easy and then when attempting to go to first it very often won't go. Pushing into second from neutral no problem.
I will be going into box this summer but I'll pass along what I do to get into first.
Pull clutch partially back then put in gear. Need to find right spot to get just a snick and not a crunch. Works every time.
An alternative way that works is pull clutch all the way, hold up change lever with boot then slowly release clutch and it will snick into gear.
Somehow having the clutch partly engaged allows the gear to engage.

This may not work for you but it does for me.

What about layshaft shimming? Would too little endplay in the layshaft cause these symptoms? I have rebuilt three of these AMC gearboxes and two of them (on my Commando and Dominator 88) shift like butter and the third (Matchless G12) has exactly the symptoms you describe. Difficult to get into first once the gearbox heats up a bit. Not impossible to get it into gear, but not perfect. All three boxes had perfect internals as far as I could tell at the time. When assembling these boxes, I followed Fred Eaton's excellent instructions except that I did not have a dial gauge to measure layshaft endplay. So I guesstimated the endplay. I plan to disassemble the G12 box at some point and reduce the size of the shims slightly to see if that cures the problem.

I done 3 things that extended very nice shifting trannies, put 3 sleeve bushes instead of two to slide around, assemble W/O any gaskets so nil layshaft slack to shim and run non Type F ATF so the sleeve bushes can get some better lube and heat removal when out of lower gears or sitting still. One delight is the one snick finding N from 1st or 2nd, so slick never sure its in N so ease out clutch just to be safe. One other little habit I've taken up is to paint the parts in the outer cover that remain above oil level.

Oh Ugh, just flashed back on another fault to check, it only take One Over Tight Primary Chain Event, to bend the shafts to slightly candy cane-ish. Not very sweet workings no matter what till shafts straightened out.

Not Norton, just example shaft sense of what can happen.

Who shifts into neutral on the road? I thought everybody held in the clutch.

I wanna be able to make a quick get away (or better - get OUTTA the way)
in case something wierd happens at a stoplight.
Like yesterday when the guy approaching from behind didn't see me and I had to jump the curb!!

rx7171 said:

I'll pass along what I do to get into first.
Pull clutch partially back then put in gear. Need to find right spot to get just a snick and not a crunch. Works every time.
An alternative way that works is pull clutch all the way, hold up change lever with boot then slowly release clutch and it will snick into gear.
Somehow having the clutch partly engaged allows the gear to engage.

This may not work for you but it does for me.

Click to expand...

Exactly what mine does. If i pull the clutch, shift from neutral to 1st, push the bike forward or back just a bit there's a snick and she's ready to go. Interesting. Don't have the time to do the full rebuild of the gearbox yet but this little trick will get me through.

roqueweiler said:

Who shifts into neutral on the road? I thought everybody held in the clutch.

I wanna be able to make a quick get away (or better - get OUTTA the way)
in case something wierd happens at a stoplight.
Like yesterday when the guy approaching from behind didn't see me and I had to jump the curb!!

Click to expand...

Sometimes clutch cables break quickly. That could lurch you unexpectedly into oncoming traffic.

Its not a good practice to hold clutch in longer than needed to remain still as puts strain on clutch center,cable and gizmos it works. But if tranny a bother to shift about thoughtlessly then sure I'd hold clutch in as long as needed to keep riding till it become a show stopper. I've had clutch cable break but hadn't occurred to me about stop light launch while still red. Its also ancient tradition to shift in N at stops with the ole foot clutch bikes, if bike tipped that side and a foot put down in reflex... Suicide Clutch became a nick name for this design. Long distance riders tend to run two cables for a quick change on hand.

Sometimes clutch cables break quickly. That could lurch you unexpectedly into oncoming traffic.

Click to expand...

Great........something else I hadn't thought of that I need to worry about ;-)

I guess I'll be checking my clutch cable regularly (sigh)

They tend to break at lever knob so is practical to check now and then but wears so long ya tend to forget about them till nothing happens as expected. It almost practical in my low traffic area to get home w/o clutch but its nerve wracking to get into 1st if stopped. Once moving its a no issue to shift up or down by just lightly matching rpm and loads till gears just fall into place w/o jerks are shocks. I've put vice grips on one clutch cable to pull on to get going and on throttle too but better to wrap loose end on throttle grip and trap with thumb. Some even carry cable end repair kits.

xbacksideslider said:

Sometimes clutch cables break quickly. That could lurch you unexpectedly into oncoming traffic.

Click to expand...

Indeed. One of the old warnings I can't get out of my head to this day was about holding the clutch in while having fun blipping the throttle to hear that engine - if fate decides you're the most unlucky SOB on the planet and the cable breaks just as you dial in about 3K at a busy intersection .......ahh, the imagination balks.

roqueweiler said:

Who shifts into neutral on the road? I thought everybody held in the clutch.

I wanna be able to make a quick get away (or better - get OUTTA the way)
in case something wierd happens at a stoplight.
Like yesterday when the guy approaching from behind didn't see me and I had to jump the curb!!

Click to expand...

A concern I have is if sitting for a while at a light with the clutch pulled the adjuster at the clutch rod is pressing with serious pressure while spinning so even with lube I'm concerned about wear.

I'm not so sure there is anything wrong with a "crash " gearbox that won't go into gear
at a standstill. Apart from being annoying.
Many many non synchromeshed gear boxes do just that.
May be gearbox oil, may be clutch adjustment or worn shafts.
But also, if the cog needs to spin slightly to engage, then there may not really be a problem.
Many a time I've had to lift my foot off the clutch pedal slightly so as to engage a gear, any gear,
not just first, in a large truck. Trucks are fitted with clutch brakes to assist in first gear selection
but sometimes need a help, by allowing the gearbox to turn a bit.
My bike does it very rearly, I just slip the clutch a bit.
One thing I have notticed with Norton gear boxes, is that they generally snick into gear quietly, unlike
Japanese gearboxes that tend to shake the whole drive train.
I always go for neutral at the lights, now that I'm sure Ed will idle properly, and often I need to
release the clutch a little after snicking first, just to be sure it went in.
AC.