84 Honda 125M Shifting out of sync after Shift Drum Stopper broke off

[pachouly1956]

I have a Honda 125M ATC that the tower or boss that holds the Shift Drum Stopper was broke off. Thankfully JB Weld is holding it, but the shifting is out of sync. The neutral indicator is pointing straight down when it is neutral. Is there a way to get back in sync without splitting the crankcase?

[Howdy]

Not quite sure what part your talking about.

[Jason125m]

I've been looking on the schematics trying to figure it out, the same case " boss " broke off on my 125m two years ago, i didn't trust jb weld so I had to buy a new case.
I don't understand what you mean when you say out of sync though ?

[pachouly1956]

If my photo up loaded this is the posistion of the neutral indacator when the trike is in neutral.
The trike was repeatedly shifted after the Shift Drum Stopper was broke off.Is it possible that the shift drum is a revolution off?

[Jason125m]

if the machine still shifts fine I would leave it be!

[Jon Boy]

if that's all your talking about you can remove the clip on the little white indicator and pull it off then spin it to the correct postion, stick it back on and replace the clip.

[kb0nly]

^ What Jon Boy said....

You can get off like that when there is no stopper to prevent it from moving, as long as its grabbing all the gears your ok. I doubt JB Weld will hold though, i have seen it done on them before. I have had a 110 and a 125 with that very problem now. I got lucky as you did and found all the pieces and then had a local shop weld the piece back on, still holding up to this day.

[sammiefish]

having a 125m Im interested but dont understand just where the damage is....
do you have a picture... also confused by what you mean by shift drum stopper...
is this internal?? how did it happen... kids or big guys??

[kb0nly]

sammie...

The shift drum stopper is internal under the right cover. When you shift and release the shifter the spring loaded stopper arm holds it in gear so the shift drum can't turn. Its a very common failure on the 110/125 motors. Its not due to kids, big riders, abuse, they just fail as they are a weak point. The stopper is still available brand new and i have bought and replaced a few, the part has weak point in it that usually breaks. I think the spring is honestly too strong and causes the fatigue on the parts and also the harder shifting on some of them. I played around with the spring on one, bending and heating it a bit to remove some of the tension, it then shifted smoothly and didn't require as much force.

The problem is the shift stopper sits on an aluminum boss on the case casting, its a bit of a weak spot and cracks and eventually just breaks if the stopper gets jammed hard when it breaks.

I don't have a good picture of it, but you can look at the diagrams in the service manual.

[sammiefish]

is this shift stopper here in the drum assy pic? #8 maybe??

[elgoatropo]

sammie...

The shift drum stopper is internal under the right cover. When you shift and release the shifter the spring loaded stopper arm holds it in gear so the shift drum can't turn. Its a very common failure on the 110/125 motors. Its not due to kids, big riders, abuse, they just fail as they are a weak point. The stopper is still available brand new and i have bought and replaced a few, the part has weak point in it that usually breaks. I think the spring is honestly too strong and causes the fatigue on the parts and also the harder shifting on some of them. I played around with the spring on one, bending and heating it a bit to remove some of the tension, it then shifted smoothly and didn't require as much force.

The problem is the shift stopper sits on an aluminum boss on the case casting, its a bit of a weak spot and cracks and eventually just breaks if the stopper gets jammed hard when it breaks.

I don't have a good picture of it, but you can look at the diagrams in the service manual.

KBOnly, Is this drum stopper breakage more of a 125 thing than a 110 thing? I fixed my 125 boss with a longer bolt and JBWeld pooled up high, flush with the top of the boss. It's been good for a couple years. I'm curious, because the 110s seem to run forever, but most of the 125s are toast by now, and I'm wondering if the drum stopper is the reason. It looks to me like the bolt might have loosened up, backed out, and got caught by the large pinion gear, ripping the boss out, but not sure. Have you seen this happen on a 110?
Because I have one of those too, and I'm tempted to take the bolt out and loctite it real good.

[tri again]

KBOnly, Is this drum stopper breakage more of a 125 thing than a 110 thing? I fixed my 125 boss with a longer bolt and JBWeld pooled up high, flush with the top of the boss. It's been good for a couple years. I'm curious, because the 110s seem to run forever, but most of the 125s are toast by now, and I'm wondering if the drum stopper is the reason. It looks to me like the bolt might have loosened up, backed out, and got caught by the large pinion gear, ripping the boss out, but not sure. Have you seen this happen on a 110?
Because I have one of those too, and I'm tempted to take the bolt out and loctite it real good.

See if the search key works for "125 shift" or shift drum etc etc.
I have a 125 that broke off the boss too, posted lots of pix.
Kb did a great, extensive write up too.
I now have a 110 with the same mystery shift problem.
Either bolt is loose, bent, broken or the case 'boss' is busted off.

We run a campground so 2nd gear is all we ever need so I just took off the shifter
and reset it vertically so it's a hand shift that's impossible to STOMP on
and use like an extra footpeg.