Mk3 - Finding neutral or mods to find neutral since 1975

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p400

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I was frustrated after completing major service on my "new to me" 8000 mile Mk3 about finding neutral at a stop or light. I can find neutral most times while approaching at speed, but after stopping.....not a chance of neutral.....forced to hold the clutch lever.

In my review of period literature I came across Motorcycling Monthly November 1975 and out of that review found the following -


PERFORMANCE

Without so much as bending a law, the Commando would put up road averages of 40-plus and combine them with a fuel consumption better than that obtainable from quite a few smaller-engined bikes. A 96-mile trip from Lewes to Andover, for instance, took 140 minutes to complete on 1.8 gallons of fuel. Average speed, 41.4 mph. Consumption, 53.7 mpg. Quite creditable for a twisty journey, mainly on single-carriageway roads.

On running such as this, the Commando was as nearly single-geared as made no difference. The engine was operating nowhere near the speed at which maximum torque would be produced - nearly 85 mph - but there was ample power in top gear above 45 mph, and third looked after the rest. Tweaking the grip, in either gear, produced immediate and very satisfying acceleration with no fuss. Though top-gear vibration had been troublesome below 3,000 rpm initially, it lessened considerably during the first 1,000 miles use, and 50 mph top-gear cruising on restricted roads gradually became positively restful!

In towns,' unfortunately, it was a different story, The Commando was not and is not - a pleasant machine to use in congested areas, Really, it is under heavy traffic conditions that the Commando begins to show the age of its basic concept. Even at 20 mph in bottom gear, the engine is below the critical 3,000 rpm at which vibration becomes an annoyance. Top gear is almost impossible to engage, and even third a bit fraught, at traffic speeds. It is the old story of verticaltwin inflexibility writ large.

Unfortunately, in the Commando's case there are more snags too. The clutch is ferociously heavy and - worse - engagement of neutral with the machine at rest is guaranteed to produce an immovable pedal and a palpitating Commando stuck in first gear. The only remedy, if tentative prods at the pedal to get into neutral on the roll fail, is to cut the engine, select neutral, and then restart. Even that is sometimes more easily said than done, since the electric starter has only just enough power to swing each 414 cc cylinder over compression, and dabs on the button are not invariably successful. You then have to kick the thing and press the button at the same time, since kick-starting alone requires the leg muscles of a centre-forward allied with the weight of a young elephant ...

A commuting Commando is also thirsty. We recorded 39.8 mpg on suburbsto-centre work, compared with over 45 mpg on runs from Lewes to Central London.

HANDLING AND RIDE

Oddly, - the handling improved noticably as the mileage mounted. At first, the Commando handled as well as, but no better than, anyone of half a dozen comparable superbikes. It was safe, predictable, and reasonably accurate, It was not outstanding. But after 6,000 miles it was noticably tauter and responsive, maturing like a vintage wine.

The riding position is good; though the lack of adjustable footrests is a nuisance, and the bike does not tend to tire the rider so long as the speed is kept above the low-frequency vibration band. Also, its firm suspension gave a good ride, though track tests disclosed limitations. It coped with pave, but on washboard surfaces pushing the speed up induced steering vibration that could have become a tank-stopper. Not the bike for the outback I

We found, on the track, that with a carrier fitted the Commando would weave noticeably. Around 85 mph appeared the threshold speed for this, and above 90 mph it felt as if it might well go out of control. The oscillation disappeared if the rider crouched over the tank with knees and elbows well tucked in. Curious I .........
Continued on page 12

What has been found since 1975 to correct this Mk3 find neutral issue?

Thank you

Mk3 - Finding neutral or mods to find neutral since 1975
 
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Yup! Fix the clutch. Clean the clutch plates. Inspect the clutch hub and chain wheel for notching. Adjust the clutch properly.
 
Standard Commando clutch *should* be exceptionally light and doesn't drag (traditional cause of not getting neutral at a standstill) - the original road-test bike was clearly not up to snuff... typical 1970's Brit complacency :(
None of mine ever had this issue, and I can't pretend that I did anything clever to get the clutch right.
 
I agree. My 850 has a comfortably light clutch and finding neutral is totally painless. In fact, I use my Commando's gearbox feel as the example of how a Moto gearbox should feel. It "snicks" easily and positively into/out of gear. I suspect, as others have pointed out, that the clutch is not fully releasing and an adjustment should correct the problem.

HOWEVER, there is no telling, unless you already know, what some previous owner or mechanic may have done to the clutch with regard to stack height and type/brand of clutch discs/steels so your problem could lie there. FWIW, my 850 was put in "perfect order" by a famous US purveyor of Nortons/other Brittbikes and I discovered years later that it had a 750 pressure plate in the clutch assembly rather than the correct 850 plate. As the saying goes, "Trust but verify! ;)
 
I can't say anything about the 75 model but my 74 has a very light clutch and a nice click to find netral and out of all my bikes it has the smoothest gear change of all, its been like that since new and I think the 75 should be the same, if the clutch is adjusted right, primary chain adjusted right as well rear chain then everything should be smooth and light, if its not right then open up the clutch and give it a good clean and inspect for anything not right and don't forget to check the clutch cable and adjustment.

Ashley
 
Just wondering...the Mark III has the shift lever on the opposite side so some sort of linkage/extension is involved that is not present on earlier bikes. I have never ridden a Mark III so I have no personal experience with them. Maybe that linkage/extension has something to do with less positive shifting/finding neutral?
 
Looking at the clutch for gear engagement issues is pretty standard for any clutch on any motorcycle. Thanks to all here.
I was hoping there was a more specific action on a "left shift" Mk3. Someone who had many times resolved this exact Mk3 issue with specific action ....., not just clutch work in general consisting of warped plates, spring tension, material composition, clutch rod clearance,etc.

Maybe gearbox mods, gear shift linkage/gears/shafts, special clutch components, ideal primary lubricant.

Anybody riding a Mk3 daily and/or maintaining several Mk3 that repeat this issue that has eliminated this neutral problem?
What specifically was found and corrected on a Mk3?
 
I found Surflex friction plates (5 fibre plate kit) certainly improved neutral selection compared to bronze plates.
 
Finding neutral is no different on an MKIII as long as the clutch fully disengages and there is no other mechanical issue preventing distinct linkage movements. Yes, the linkage makes them feel a little different but they do work.
 
I also have the Surflex friction plates, the type with the pads bonded to steel tangs.
They are bathed in engine oil, 20W50, at the manual specified level.
As long as the plates free up there should be happy neutral finding.
All the best.
 
Light clutch and easy neutral find with my MK3. Also, no clunk when putting it into first,unlike about ten various Vintage bikes that were fired up then roared off yesterday here at the "Over the Pass Rally" in Winthrop.
Type F in the primary ( some say don't do)
Barnett Kevlar plates
DynoDave seal
Stack height set by DynoDave's info
Venhills Featherlight cable.

So many little nuances or changes that make it work properly, but once you get there it is a lovely clutch that doesn't slip,grab or drag and can be pulled in with one finger.
When I first got the bike neutral was impossible to find when running and the clutch pull was horrendous.
 
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