Fuji Robin Engine Spec to build Robin Enfield

[brucey]

Following on from my introduction to this forum, I thought I would start another thread on my Enfield Robin Diesel build project.

I started going through all the Robin Enfield bits last night and give or take, I probably have enough conversion parts to build around 5 bikes. I have a lot more of some bits (engine plates, covers etc.) but they need welding together.
I have a complete Enfield Gearbox and Primary Drive Backing Plate assembled onto a Robin Flywheel Cover. There must be at least 15 other smaller components in the conversion kit including battery boxes, brackets and covers.
I had no idea how detailed and professional a job Redbreast had done! From the production point of view, I seem to have most of the welding Jigs and Fixtures to assemble the main components.


Before I get too carried away with buying a 350 Enfield and cutting it up (there seem plenty about) I need to source probably 2 good engines. Bearing all the above in mind, I have decided to go for a Robin DY42 unit as this is the most powerful option for the parts I have.

I am still not 100% sure what spec engine I need as I haven't found any order information or specifications relating to engines in the documentation I received. I am assuming the following:

Robin DY42D (output 9.4 hp @ 3600 rpm). Could a DY30 or DY41 be upgraded?
Electric Start option Can this be added to a non electric start unit if required? (I think the Crank Cases have different part numbers).
12V-30W Lighting capacity (option) Is this enough to run an Enfield electrics? I think I have seen these coils available on E Bay.
Counter Balance Shaft? Are these standard?

I also know Redbreast Industrial Equipment used to lighten the fly wheel but I do not know how much or where. I do have some big turned rings but am not sure if they are Flywheels.

Midland Machinery have 2 Robin DY42 engines in stock but they are recoil start. It may be a costly exercise getting them to the required specification.

Any help or advice would be appreciated.

brucey

[pietenpol2002]

These lads in Bristol still list the DY42 on their website, but not cheap. And who knows if they indeed have it in stock or if it's the electric start.

http://www.diyspareparts.com/parts/bell ... in-291244/

I think you're correct about desiring the D model as the B model comes with the reduction drive. You might be able to get the flywheel dimensions from tonyd here on the board as those mods might have been done to his Robin/Matchless.

[brucey]

Thanks for the info Ron.

I had a quick look at the website and was pleased to see they are based in Bristol UK as I think there is probably in Bristol in the USA somewhere!

If I knew I could retro fit an electric starter to a pull start DY42, I would be a bit happier buying a second hand motor with recoil start only.

I have spent most of the day sorting through more of the bits I bought and trying to find out where they all go! I think I need a bigger shed.

Having no experience with Royal Enfield's I'm not sure if I should just buy the cheapest 350 Bullet on e bay. I still like the idea of a trials style bike but a single seat and a set of new rims (I found a load of spoke nipples in the spares) would get me close.

If I can contact a guy called Wayne Marlow who used to build the Robin Engines for Redbreast Industrial back in the 90's, I'm sure I could get most of my answers. Unfortunately he has left the industry. I have messaged 3 Wayne Marlow's on Face Book just in case!

It's starting to look a bit daunting but I'm sure I'll plough my way though it when I get my hands on a bike and diesel engine.

brucey

[gilburton]

In general terms if you can get hold of ANY dy41/42 cheaply in any condition buy them for spares if nothing else.I speak from experience!!
A year or so ago I missed out on 2 engines that sold for around £50 each because I couldn't get down to collect them
As I've said the DY41 is physically identical to the DY42 with or without the starter so as far as getting on with your build ANY of these engines will do for a mock up. Even a tatty rough example!
Go for the electric start model for your final build if you can find one. My bike was cvt so when the starter went I had no means of starting . You will have a kick starter but I believe it was still difficult to kick the robin??
I never used the decompressor as a 14A battery was sufficient. (yb14-A2)
I'm not sure about the crankcases as I've never seen a pull starter one up close and you will also need the ring gear which is bolted on inside the flywheel. I know a starter costs around £250 so I should think it will be near £500 to convert so it's not worth it assuming you could drill the cases?
If you study the parts list in detail the head,barrel,crank is the same for both models and the only difference I can see is the piston? Even this must fit all barrels as the barrel is the same so the difference must be in the chamber on the piston crown? and not in stroke or overbored barrel.
You will also want one with the 1" or 25mm straight keyed shaft . If you want to buy one of these it's £75
I just used the standard flywheel(which is VERY heavy) so I can't help with your "rings"?? Was the standard flywheel machined down and a ring bolted on to the original centre??
As far as a bike is concerned I should imagine any Enfield older than the years in which the diesel version was produced will be ok.
You'll be scouring agricultural type shows and rallies for info/spares at autojumbles etc
Might be worth contacting any stationary engine clubs in your area??

[sbrumby]

There was a previous post on the robin starter. But I will repeat, a friend had a Robin engine, the starter was replaced and a few weeks later the engine went kaput this was scraped but the starter was kept. I think he wants about £80.

[brucey]

Cheers Guys,

Looking at a £900 Enfield on e bay at the moment but may wait until further on into the winter

I have another possible source for new Robin Engines which is Meetens in Gosport. I will e mail them with my requirements.

Sam,
Can you give me some contact details for your friend with the Robin Starter?


Brucey

[gilburton]

Have you seen this??
http://www.ebay.co.uk/itm/royal-enfield ... 23312854ad

[pietenpol2002]

Nice find. It appears he might also have the NOS Robin diesel exhaust down pipe listed. As well as the side covers.