Enfield and Harley (Ultima) Gearboxes

[Diesel Dave]

For those of you that are considering or are using Enfield gearboxes (the old 4 speeders) I have a bit of an info update for you.

Old Sluggy has such a gearbox with a Lombardini 6LD400 engine strapped to the front of it. It has the longer shaft usually used for the Enfield diesel conversions and this being 40mm longer puts a lot of extra strain on the bearings. It also has a close ratio gearset which is a little expensive bit well worthwhile if you live in a hilly area and have little engine HP.

Now last week the gearbox jammed in 2nd, so this weekend was the first opportunity to investigate the problem.

The great thing about the 4 speeders is the simplicity - don't worry if you have never taken one apart before they are really simple (it was designed for use in a lathe). Unlike jappo boxes it has an external ratchet mechanism for the foot shifter so this is easily removed.

The cause of my problem was a spring loaded detent that locates each gear in position, this has shot out of it's barrel and jammed the shifter.

Whilst the box was apart I took the opportunity to inspect the layshaft bushes that are very prone to wear and sure enough they have a HUGE amount of play in them. Interestingly the original Indian bearings were fine despite the longer shaft placing more load on them and the use of oil instead of the factory filled grease. - It never leaked either despite all the stories about needing to use sealed bearings!

So I have some new parts on order and Sluggy should be roadworthy once more by Thursday.

Harley (Ultima) gearboxes.

With Sluggy off the road it was up to the new Tiger to fill in for commuting duties - jeez it's big!

I have been really impressed by the aftermarket Ultima 6 speeder gearbox it has a really positive shift and the ratio's are nice and close for a diesel.

As expected the dry clutch rattles like a Ducati but you can't have everything!

The engine is still as tight as a Witches tit but it should come good in about 5000 miles.

Keep that faith folks
Dave

[LocomotiveBreath]

Speaking of harley/ultima transmissions, I've been looking to ax the centifigual clutch in my scooter asap. Jireh cycles has the best deal here in the states for a 6 speed@ $559.00 US.
http://www.jirehcycles.com/

[Anorak_ian]

Hi Dave, thanks for posting this, I was unaware of just how bad the cast iron bushes were.

Was your box new when you got it?
If not maybe the bearings had been replaced but not the bushes.

Anyhow, I guess you know already, (but for those who don't) if you go to Hitchcock's website you can get the British made bronze bushes for both ends of the lay shaft, they cost a little more but are said to be a lot better.
In my old British box I couldn't tell the difference between the old bronze bush and the new one I'd replaced it with, this maybe a sign that bronze does a damn good job, or maybe some kind soul replaced it before I got the box.

How have you got the kick start bush out, I have to drill them out, I'm sure there must be a better way.

[Diesel Dave]

The new bushes have been supplied as Phosphor Bronze by Hitchcocks.

I did actually want a new set of cast iron ones, but nobody orders them apparently.

You have to be really careful with the oil you choose with this material as modern gear oils dissolve out some of the metal.

The only gear oil I know that's suitable in the UK is the classic Morrisons brand - expensive too but at least it's available in EP140 grade!

Cheers
Dave

[Anorak_ian]

Yes it's odd isn't it that Hitchcock's are selling the cast iron bush for £17+t+p&p, when they sell the brass bush for £11+t+p&p.
I guess that they are making the brass jobs and over pricing the cast ones.

You can get the cast bushes from Royal in India, they sell on eBay for £6.99+2.50p&p, and this is for both left hand case end bushes (shaft bush and case bush). Unfortunately they do not sell the kick start bush unless in a kit, but Hitchcock’s sell them for £2.20+t+p&p.

I did hear about the problem with the oil, but I thought it was the old ep80 ep90. I'll ask Hitchcock's to make sure.

How many miles has your box done?

[Diesel Dave]

Hi Ian,

It's the EP rated oils that have the problem especially if water is present (and it will be in the UK).

Good old fashoned straight SAE ratings are fine and at least don't smell like an old tomcat either.

Seagull outboard motor gearboxes used SAE140 so it is available out there.

This box has only been in the bike for about 5 months, I swapped it after returning from the Hamm rally in Sept but it was of unknown vintage having sat on a scrappy's shelf for many a year. I suspect it's an early 90's box.

I have a little wheeze for removing the blind bush in the kickstarter shaft, I'll make sure it works before posting up though.

A mate did suggest I replaced the bearings and bushes at the time, I had it apart to fit the longer shaft but of course I knew better.

There is an easy check to see if the internals are fine - check the casing temp asfter a long ride - if it's hot then there's friction inside - usually caused by the shafts being allowed to push apart by worn bushes and bearings.