Forum

[Alan R]

Hi guys--------has anyone renewed the gear-change centralising springs on one of these 5-speed boxes before ?? Looking at our hosts schematics there would appear to be TWO of them !!ie one within the foot-operated selector mechanism and one forming the detent function onto the outside edge of the cam-plate. I'm told the symptoms are }----Up-change is positive ok, Down-change is "wooly" with missed gears all the time. Power transmission is positive at all times with no undue groaning etc when idling OR under power. It's got 4,000 miles on the clock and in all other respects is ok. Passed an Mot to-day with no advisories. Will the shaft assemblies have to come out to access the detent spring ? Thanks a million---------have a good Bank Hols.

[Kmac]

Hi Alan
I have worked on a low mileage 5 speed gearbox.
The symptoms with that one was that up changes were ok, but down changing was intermittent. This is due to the change lever not returning positively back to it's neutral position.
The spring at fault was the hair type spring that sits on the end of the cam shaft ( items 20 &. 22 on the 5 speed gearbox parts List). It is easily accessible after removing the outer cover.
The tubular cam shaft pivots on two stub shafts on either end of the cam shaft. These have 5 mm tapped holes to enable them to be removed.
The new spring obtained from our host was exactly the same as the one that came out.
The original was used but the two ends were over bent to give the spring more strength.

kmac

[Kmac]

Alan. Where I said cam shaft read that as rocker shaft ( item 22)

[Norm]

Alan,
My 5 speed did this when I converted it to right shift. I made a small bracket attatched to the shifter pinch bolt, hooked a spring onto it and hooked the other end down under the box and onto the frame and never had a problem since

[Alan R]

Hello both & thanks for the swift replies.I have down-loaded the schematics from our hosts and printed and expanded. Yes, it looks just like any other cam-plate type of change mech. with 3 forks to get the 5 speeds. On our Army CVRT (Scorpion)vehicles the g'box is a 3-speed epicyclic, with a 4th drum to give a High/Low range and a multiplate clutch to lock-up the whole train. Thus 14 speeds were avilable. This was hydraulically operated by a sequential selector which had exactly the same type of "Hairclip" spring assisting the operating lever. This had a habit of breaking if the name of the day had a Y in it !! So all that VERY EXPENSIVE kit went AWOL if a 50pence spring had a "headache!!" Needless to say it was changed each time regardless. I guessed it might be this one also----I've got the bike in next week. Right now I'm more of a counsellor to my mate who's just collected it and this happens. You need a degree in Psychology don't you ?? Thanks----will keep you posted.

[Norm]

Alan, what the shifter has to do is release up and if you play with the shifter you can actually feel it click if you lift the shifter a fraction. It will not change gears if you don't feel this click. The spring is obviously close to the limit so any slight increase in resistance and it won't lift that fraction more. As I said a small spring attatched to the rear of the shifter fixes the problem. Before I fitted the spring I had to get my toe under the shifter, lift it a fraction before I could change down a gear

[Kmac]

Norm. I agree exactly with your description of symptoms! The spring is of very dubious quality and can only just be described as a spring!
Another solution I considered was the old italion favourite, a heel and toe gear shifter.
I think the factory are well aware of this problem as most of the home Market machines with this box are provided wiha heel and toe gear lever