Royal Enfield Owners Club,  Humberside Area
Back to the
Homepage
 

Royal Enfield Classic Bullet

Flexing gearbox outer cover on Indian models.
My fix.

 

It's well known that the gearbox outer cover of the four speed Albion type gearbox is not strong enough.
It flexes outwards as the clutch is disengaged. Early Indian classics were pretty bad but even late models suffered from the problem to some extent.

This in itself wouldn't be a problem, but this couple of millimeters flex robs the clutch push rod of that amount of movement and the mechanism is short of movement as it is. This is one reason that the RE classic clutch can be tricky to set up correctly and can start to drag when it gets hot (e.g. in traffic)

Obviously it's a good idea to eliminate this movement if you can.
Hitchcocks will sell you a special replacement cover which will do the job for about 170....................
Or you could do it yourself.

One way is to extend one of the main bearing bolts out through the cover but I think the hole you need to drill in the cover is a bit close to the inspection hole for comfort.
Another way is to use an offset stud to utilise the neutral finder bolt hole. It seemed to me I would have to drill out the treads on the neutral finder bolt hole to do this and I wanted to make the job reversible if it didn't work.

This is what I did;

 

Steel strip mounted on brass spacers between the main bearing cap bolt and the inner cover fixing screw ( with suitable longer screws)

 

20mm X 3mm steel strip drilled at each end 1/4" with 6mm tapped hole at centre.
Top hole has to be pretty near the edge to clear the clutch lever.

 

 

Brass spacers 1/2" OD,  1/4" ID
I used brass for the spacers because I can work it easily on my woodworking lathe with ordinary HSS wood tools. Cutting is not really possible, but drilling and scraping and filing are easy if you take your time.  (I don't have a metal lathe)

 

Drilling the cover. I drilled at the centre of the cast-in webs as I thought it might be strongest there.
This, of course, isn't reversible but could be filled with a short nut and bolt.

 

I used a button headed screw  to keep the profile as low as possible to clear the neutral finder.
I used a fairly large washer to spread the load (probably not necessary)

 

Clears the neutral finder lever nicely.

 

 

I'm quite surprised there's room for this under the cover but nothing fouls so I'll call it good.
It's certainly cut down the flex on the cover. It's still there but much reduced.

UPDATE 1000 miles on
This mod has been a complete success. I've not had to adjust the clutch cable since I did it (this used to be a regular chore) and the gear change is a lot sweeter (well, as sweet as an Albion box gets anyway)

UPDATE 2013

Hitchcocks are now selling a version of this mod for 15 (but it's more satisfying to DIY)