help for upgrade to 436 cc

[dieselbikerindia]

hi im jai singh
from india
i have already introduced myself in the member introductions

my diesel bike is
Enfield 325 cc(78x88-greaves) diesel
4 speed gear box..and
4 clutch plates clutch
18 tooth spocket in the front and standard in the rear..

the bikes does a 75 kph on the enfield speedo and gives 50 kpl
pretty fun to drive but some more things are in plan..basically to make a setup which cruises at 100kph
does a trip high in the mountains like ladakh
is reliable and
of course economical as well

following are the mods in my mind:

upgrade the engine
the choices that are available in india are :-
greaves 395 (86x68)available in the piaggio three wheeler (euro 2 model)
greaves 436 (86x75)available in the piaggio three wheeler (euro 3 model)
(the external size and mouting are same as 325cc motor)

greaves 436 as claimed by piaggio gives better performance than greaves 395

upgrade the GB
the only choice is 5 speed GB conversion for which i have the gear box,
this is already done on my enfield 535 with a RH shifter
with the 5 speed GB the power loss will be minimum.

upgrade the clutch
clutch upgrade from 4 clutch plate to 5 clutch plate
already done on my enfiled 535 and i know that with a bigger diesel motor i need to address the slippage issues.

upgrade the front brakes
present setup runs a drum brakes of enfield
which are not that efficient
plan to to disc brakes..


If all of the above is achieved and the bike is running fine
then two more upgardes in line

A turbo charger for the engine- I HAVE NO CLUE ABOUT IT..

A oil cooler for the engine
piaggio in india have three wheeler running on LPG and the basic powerplat used is a greaves 395 cc (Euro 1) motor with mods to run the LPG this has a oil cooler fitted near the engine plate above the fly wheel

This is my exhaustive plan
please help me and give your valuable inputs for my build
Thanks..
dieselbikerindia

[dieselbikerindia]

help needed for:-
1. 5 speed gearbox upgrade primarily what is the difference like main shaft and mountings etc
2. If iam not changing the gearing of the 5 speed gear box then where all can I vary the gearing and what are the best options available
primary clutch drive????
front spocket ????
rear spocket i intend to keep stock....

[nanno]

I can't help you with the 5-speed, but yes, you can change the front-sprocket for a bigger one. In overall topspeed, the 5-speed will not give you any benefits, because the final transmission is the same as on the 4-speed, only the gap between 2nd and 3rd is smaller, because that's where (IIRC) the additional gear is.

Cheers,
Greg

[dieselbikerindia]

thanks greg
what kind of front sprocket are u talking about
there are two options easily available here in india
i am running a 18 tooth front sprocket of the four speed gear box (dull coloured and comes with collar support)
the same sprocket for 5 speed gear box is 18 tooth (shiny look without collar support)

to what number of tooth i should experiment...for thr front sprocket

[nanno]

I will run an 18 or 19 tooth sprocket on my 325, when changing the chain, because it lowers the revs and (although I live in Austria) there's not too many mountains on my daily commute. (And quite frankly, I will soon start work on a bigger and stronger Diesel to be honest for overland use...)

Cheers,
Greg

[dieselbikerindia]

hi greg
same here im planning to make my bike a mountain commuter
the himalayas range from a average ht of 7000 feet to 18500 feet on the highest point.
the challenge is to put a bigger engine+better gear box+upgarde the clutch to 5 plates..

[dieselbikerindia]

guys need help!!!
i am the first person in india doing the 5 speed conversion on a diesel enfield
in the forum many members might have already done that
my plan rt now is three things
1. engine swap from 325 greaves to 436 greaves(engine available)
2. gearbox swap from 4 speed to 5 speed with RH shifter(5 speed GB available)
3. clutch upgrade from 4 clutch to five clutch

There are issues what i can think of are:
1. A longer main shaft for the 5 speed gear box(not the welded one)
2. Fixing the teeth of the front sprocket and the primary drive (keeping the rear sprocket stock)
3. Is there any requirement of any offset front sprocket ?
4. Any other input from members who have already gone through this conversion..

The guidance would help me out to make the first 5 speed 436 cc diesel in india

Thanks..

[Diesel Dave]

To do the 4 to 5 seed comversion you need a 40mm longer gearbox shaft and also convert the shifter to a right foot operation

Everything else is just nuts and bolts.

The 425 engine does vibrate a lot more, but the mountings are the same.

[dieselbikerindia]

thanks for the input
the right hand shifter is sorted out
i need the longer shaft +4mm for the 5 speed NOT AVAILABLE IN INDIA !!
only 4 speed GB longer shaft available because of the diesel TAURUS model...
can I get directions in this regard..

[dieselbikerindia]

for the vibrations
my bike is a sooraj chasis and is more crude but more robust than the enfield taurus chasis..(equivalent vibrations are less)..

[Diesel Dave]

Henry Price can get a longer shaft in the UK.......

But they are made in India?

[dieselbikerindia]

5 speed longer shaft for diesel conversion
can somebody help me on this
where to procure it from..(not the henry price one)

[nanno]

You will probably have to knock one up yourself on a lathe. I.e. weld in a piece (or get it done by a professional machinist).

Cheers,
Greg

[dieselbikerindia]

u mean to weld a standard 5 speed shaft to longer length..?

[nanno]

Yes.

[dieselbikerindia]

thanks ..

[dieselbikerindia]

what i understand is
take a standard 5 speed shaft
take a diesel 4 speed shaft (longer one)
and then do the machining job?

[Diesel Dave]

If you want it to be reliable then don't try welding 2 parts together, you need to get a longer shaft made up from decent steel, EN38 or similar.

Also consider using an outrigger bearing to support the longer shaft.

[dieselbikerindia]

thanks dave
for the input..
can you plz let me know
from where i can buy this setup..
since i am the first chap to do the 5 speed conversion on a diesel in india
so i would be easier if you can help me in buying this shaft..
can you please tell me more about this outrigger bearing..?
thanks..

[Diesel Dave]

I'm afraid I have no idea where you could buy such a setup in India.

I would look for a local engineering shop and take along a 5 speed shaft and ask them to make up a 40mm longer version.

Outrigger bearings are useful to support the longer shaft, again if your new to engineering then your going to need a local engineer to advise how you can do this as it needs fabrication.

[dieselbikerindia]

thanks for the help dave

[UnclearFizzyCyst]

Have you considered keeping the 4 speed GB and fitting the 'trials' gearing from Hitchcock Motorcycles (in the UK)? This would give you something for the steep bits but retain the 1:1 4th gear ratio. You could then play around with the drive sprocket teeth count to find your best option.