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I have a scoot in for a bit of fettling and the gear change is SO stiff. So what have I tried so far?

Taken the gearbox out so I am just trying to move the cursor, not select the gears
Replaced both gear cables so there is a smooth operation of the swivel and tie-rod with the tie-rod disconnected.
Checked the balls and spring in the layshaft (it looks like a standard spring, which I prefer)
The gear selection arm moves smoothly with the cursor disconnected.

However, it is still stiff at the handlebars.

I did find that the cursor was a bit sticky on the layshaft i(in gears one and two) in two of the three possible positions that the cursors can be rotated to fit but still it is a handful at the handlebars. The cursor is good because it works well on another layshaft I have.

Any thoughts or suggestions?

What about adjusting the clutch? Or maybe you’ve done that.

The clutch and gear box are both out of the scooter.

You really need both hands on the gear control on the headset to be certain of selecting the correct cursor position.

I have tried a new cursor now. It is not quite as bad but it could be better

With the tie rod dissconnected from the selector shaft, there should be negligible resistance operating the gear change at the handle bars. Worn out cables and any binding under the handle bar gear change housing will be amplified under load.
All too often this gets overlooked.

The new cables are smooth.

I do wonder if the spring is a stronger one, but I changed the cursor last night and it did seem easier to select.

I will have another play this morning and see how it feels.With so much disconnected, the action seems a little out-of-context, if you see what I mean.

Not 100% sure about this, but I'd expect any problems in the cables not to be apparent if the tie rod isn't connected. A bit like a blockage in a hydraulic system; with no flow, it will look like full pressure is available but once flow starts, it can drop close to zero.

Leaving the gear cables free to flap around makes them much easier, just as with the clutch. I also route the cables "incorrectly" past the engine mount to give a straighter pull at the adjuster block; this definitely makes them work better but seems to upset some people.

Thanks Dickie.

I am happy with the route of the cables: nice and flowing and there is negligible friction in their operation.

Having “felt” it again in the cold light of day, it is still too stiff so I am going to order a replacement selector spring, just in case the one that was in the engine was one of the “race” ones fitted by people who believe that stiffer springs cure gear-jumping.

I had this once after fitting a new SIL sliding dog. When I took it off to examine it, I noticed that it was roughly machined which meant that the ball bearings did not have an easy ride. I replaced the sliding dog with an Italian MEC EUR one and all was good.

To add my twopennyworth....

Indian cases are more likely to have manufacturing deficiencies so the cursor bearing holes may be out of line.

I've never found a cursor as well made as OEM Innocenti/Serveta & have resorted to knocking up a jig for grinding back the driving dog faces to be able to re-use decades old items. Believe it or not, remade cursors with questionable quality control allow the relevant individual legs to spring out due to the cursor spring force. Besides that, even the SIL cursors were machined wrongly, easily evident with the dogs out of line when viewing them in first gear.

The selector spring is a critical choice. 'Race' items may need shortening to function & even then, due to material choice, they may easily lose their 'temper' & go soft. Of all the remade, stronger springs, LTH were my favourite.

Is a stronger spring a better spring? If so, please explain why.

I was under the impression, though very happy to be corrected, that there were only currently 3 manufacturers of 4-speed gear selectors: SIL, DRT and FA Italia. SIL and DRT make a version each and FA Italia make 2 versions that are then branded as Casa, Evergreen/TS, Tutto/Stratos, Ricambi Rapido, Mec Eur, etc...

Regarding gear selector spring strength, Harald at MMW put together this very detailed comparison. It also compares the tolerances in aftermarket layshaft production.

I had this a few years ago and what cured mine was putting bush in the lower location hole of the shaft the wishbone part rotates about.

The vertical shaft was very sloppy in the lower part of the hole in the casing.

When you selected the gets the shaft twisted in the hole rather than turning.

I had to drill and ream the casing out to 12mm and fit a split bush coupled with the new bush already fitted at the top.

After that you could turn it no problems at all to select gears easily.

Blimey Leotech, let’s hope it doesn’t come to that.

The new spring might arrive tomorrow, which sounds a good deal less painful than a good shafting

Knowledge wrote:I have a scoot in for a bit of fettling and the gear change is SO stiff. So what have I tried so fa

However, it is still stiff at the handlebars.

Any thoughts or suggestions?

probably too obvious but , ive just fitted a BGM throttle ang gear wheel to a mates Scoot and had to file quite a bit of Ali off the headset bottom to get it to fit, having road tested it, i should have filed a bit ore off as it`s too stiff for my liking .

Knowledge wrote:Is a stronger spring a better spring? If so, please explain why.

A stronger cursor spring should help maintain selection of the gear by resisting the tendency for the cursor to move sideways whilst under load/torque.

I was not aware that cursors had a tendency to move under load. I have not had that experience.

Anyway, I have fitted the standard spring and the gear selection is much, much easier.

Now to road test it to make sure it doesn’t jump out of gear. Thanks for your help everyone.

Knowledge wrote:I was not aware that cursors had a tendency to move under load. I have not had that experience.

As previously stated:

"Believe it or not, remade cursors with questionable quality control allow the relevant individual legs to spring out due to the cursor spring force"

Yet another reminder of just how good OEM standards used to be That's why I am cynical of many of the 'new, improved products' that come to market, some downright dangerous, such as certain rear hub bearings

Whilst on the subject of the chain of components involved in gear selection, I suggest the bling alloy components may look trick, but given the inherent vibration, the holes within soon become sloppy.....

A couple of points that I would add, although better reading through previous (not done) might rule out:

1. Clutch lever choice, the limited range of some levers can result in poor travel/separation, resulting in you fighting clutch and transmission when trying to change gear.

2. In Sticky's manual, there is a comment from Dean Orton about finding that some gear lever housings benefit from a little work to provide additional clearance to the clutch cable outer and passage, so that the housing and cable don't fight against one another when trying to select gears. I had never experienced such conflict and thought no more about it until I had a gear selection issue that I couldn't resolve.

Sure enough, after trying all else, I revisited the housing (never gave issue previously but I had recently replaced engine) as I noted the cable becoming stressed under rotation force, which improved gear selection dramatically!

I hadn't expected this to be an issue, as the bike had been ok to ride prior to engine replacement, and it is likely that some combination of the new motor's assembly (arm position on spines or other) and cabling was making the issue manifest itself, however, the engine assembly was right and adjustment at that end ok, but a little fettling at the headset resolved the issue.

^... Odd, but worth considering.