I think I've asked this before (drive line lash)

[GoldOxide_imp]

Hi Bob, the "play" you refer to is the engagement space between the "dogs" and the gearwheels, some of which are moving sideways on splines and others are stationary on the shaft.

The space "lash" between the dogs and the slots they engage in is required because the time involved to move the gearwheels sideways whilst rotating past each other, if there was no or very little space "lash" it would be a hard task to get the dogs to engage in the slots, so it's a compromise between easy shifting and gear "lash".

Some dogs have more teeth than others ( time for a joke here ) and the "lash" would be different for different gears, to try this out you could put the cb1100 on the centerstand and shift through some gears with the engine off to check the wheel for play by hand in the different gear positions.

The crankshaft is directly geared to the clutch and the clutch plates are engaged and together with the primary shaft and gears become part of the " flywheel ", so no play there.
The gear wheels themselves have minimal play on the splined shafts and the chain has some effect as have the rubber transmission dampers in the rear wheel, you can check those by moving the wheel back and forth in gear and look at the play between the outer and inner parts of the rear wheel hub ( the space behind the sprocket ), there should be minimal play there.

Here is a video that shows the inner workings and shortcomings of the gearbox and may provide some appreciation as to the delicate parts of the drum-shifter system;

https://www.youtube.com/watch?v=-nZjbMyIo8I

and another;
https://www.youtube.com/watch?v=L0mtwcaoXDo

Personally i tend to ride in second or third gear and freewheel with the clutch pulled in when the shudder becomes a bit much, it also sounds better for any " spectators ".

Also be aware thet the chain tightens some when you sit on the bike, if there is not enough play ( if i can push the chain up to just touch the end of the plastic guide i am happy ) the chain will tension up hard and wear out in a remarkable short time, hope this helps some

Nice video references.

[jimgl3_imp]

all due respect to Max, the CB tranny shifts clutchless smooth as butter, up and down. Sportsterdoc mentioned the cush drive. that, and / or the chain and / or the snatchy fuel injected throttle seem more likely to me, to be the cause of what he's describing. Gear lash on these bikes should be almost indiscernible. this is a Honda, not a Kawasaki.

[VLJ_imp]

My '17 EX has basically zero drivelash, and absolutely perfect throttle response. No snatchy throttle, no low-gear jerkiness...nothing whatsoever. I don't have to feather the clutch, or ride around anything. Whether taking off quickly or slowly from a dead stop, riding hard in tight switchbacks, or just tooling along in stop-and-go traffic, the entire driveline behaves perfectly.

The utter smoothness of the driveline is one of the definite saving graces of this motorcycle, the others being the excellent ride quality, and its stellar looks. I can't even imagine having any complaints about drivelash with this bike. Unless the older models are different from the '17 in this regard, all I can think is the chain isn't tight enough, or the cush drive is worn out.

[max]

Being curious i just measured the lash in all gears of the rearwheel, the first three gears are identical and have 60mm. travel ( freeplay or lash ) at circumference, the cushdrive in the hub has no play but some flexibility.

The chain has 5mm. play, that is about 10% of the total.
The chain tension is a conservative 40mm. between top and bottom movement.

As a reference the 40 year old cb550 measures 50 mm play when in first or second gear, so not much change there.

And Jim is exactly right, it shifts fine clutchless, when slowing down i apply a small amount of pressure on the gearlever, reduce throttle until it shifts down etc.

[jimgl3_imp]

the only other thing I failed to say (that I know of) is that it's a fully synchronized, constant mesh transmission. But Max obviously has far more technical knowledge than I do, so he's probably right and I'm probably wrong. I am just surprised by his findings.

[jimgl3_imp]

I don't recall how to post photos, but looked at technical drawing of the tranny. gears appear to have 5 or more dogs each, so at least they don't just have 3 like those old Kawi's in the videos. and just trivia, but I recall back in my track days, Kawi's were having to be "undercut" to make them work. I assume that means grinding off some of the gears like that guy described in the video.

[ohiorider_imp]

the only other thing I failed to say (that I know of) is that it's a fully synchronized, constant mesh transmission. But Max obviously has far more technical knowledge than I do, so he's probably right and I'm probably wrong. I am just surprised by his findings.

I don't think our CB1100 tranny would be defined a 'synchronized.' It uses shift dogs, not synchronizers, to lock an unsplined gear to a splined gear. It is absolutely a constant mesh transmission, however.

Bob

[pekingduck]

I don't recall how to post photos, but looked at technical drawing of the tranny. gears appear to have 5 or more dogs each, so at least they don't just have 3 like those old Kawi's in the videos. and just trivia, but I recall back in my track days, Kawi's were having to be "undercut" to make them work. I assume that means grinding off some of the gears like that guy described in the video.

Undercutting the gears means grinding or machining the engagement faces of the dogs, so they are tapered like the top half of an hourglass. This causes the gears to lock together under load.

[Lambchops_imp]

At that time, I think I was advised that all the CB1100 exhibit some clunking on off/on throttle, unless one 'rides around it' by feathering the clutch. I keep my chain lubed and adjusted per the book. It's not a problem, it just seems out of keeping with the overall quality feel of the rest of the bike. However, I was curious if any of the owners on the forum (or Honda) had come up with a fix.

Doubtful, I know, since it's probably in the primary drive or clutch pack.

Any thoughts?

Bob

I have the same issue on my 2013. My throttle play and chain are well adjusted within limits. It is most noticeable when closing throttle completely or suddenly at low speeds. I didn't notice it when I rode the later year models with the slipper clutch.

[the Ferret]

Chop the throttle and you will really feel it, roll the throttle and you will hardly feel it