Verify/ID 197CC SUN

[doughobbs]

Hi all,
Looking to verify this is a 197CC Villiers SUN Challenger. It was left to me after my father passed away last year, he acquired it some 46 years ago when we lived in Northern Ireland. Unfortunately I have no documents or photos of it other than a few bits of paper my dad scribbled the registration and engine/frame number on!

The front wheel is in backwards and the seat is plonked on there - this was done to keep it complete as a bike and move it about.

Codes on the bike as below:

frame (headstock): S148A
plunger (could be a casting mark?): 4-101 and a triangle symbol
base of vertical tube under the seat: S18?? (looks over stamped on the last digit)
engine: 517 7882 E
Code on base of the barrel: VJ 6 B7095A

[33d6]

Yes it is a Sun Challenger. Probably from 1953, but as all the numbers given are either incomplete or odd it’s difficult to go further.
The engine number is incomplete. It doesn’t make sense as is. It is the numbers/letters stamped on the crankcase across the top front engine mounting bosses. We might get somewhere with the full number.
I expect the frame number to be stamped up under the saddle on the left side but as the only other Sun from this period that I’ve played with was a Sun Cyclone which had the number stamped on the left upper rear suspension mounting. Then again, that had swinging arm rear suspension, not plunger. Either way the info you gave didn’t really fill the bill for identification purposes.
Have another look and try again.

[Mark M]

Sorry for this diversion, but Sun were well known for making cast iron frame fittings and other components, is the triangle mark often seen on castings, sometimes with a part number, their logo? I ask out of curiosity as it crops up on some Royal Enfield components. Other RE cast iron parts show a different logo entirely.
REgards, Mark

[doughobbs]

Here are a few more pics of frame and engine numbers, I cant seem to get a decent pic...think the camera on my phone isnt great 

Hope these help those with way more knowledge than I have...you guys are amazing!

Thanks

[33d6]

Poor pictures really aren’t a help but the single clear engine one was. The one showing the engine number. There was an A in the Villiers engine number. This makes quite a difference in identification with Villiers engines. Unfortunately not in this case as 517A isn’t on any of the remaining Villiers lists anyway and doesn’t match the known Sun numbers.

As far as frame numbers go at that time Sun used a letter code for identifying the year of manufacture and in 1953 the frame number would have started SMC-. You only have the S but as the bike is so obviously a Sun Challenger I’d accept that it is a 1953 frame.

The same records show the relevant Villiers engine number prefix for a 197cc 1953 Sun to be 339A so your 517A is a replacement engine. Nothing surprising there as for years it was common practice to replace a worn out Villiers engine with another not quite so worn used engine. These old bikes were worth so little that to recondition their Villiers engine cost more than the bike was worth so you just went to the wreckers and got another not quite so bad engine and kept riding. A full engine change took all of an hour and that included going inside for a cuppa with your girlfriend.

Sorry I can’t go any further.

[R]

Look familiar. 1953 model.

Do you have the exhaust/muffler still ?
Those headlamp brackets must be the most distinctive in motorcycling !


This bike, although incomplete and a 52 model has the plunger rear suspension.
And the exhaust system would be on the other side ?


Changed about a lot in those years, didn't they !

[33d6]

The headlight brackets are unique to the MP forks, not just Sun.
I have a distinct  lack of enthusiasm about these early MP forks. Mechanically they’re quite simple, no damping, just two pogo sticks with a wheel in between. Didn’t matter, they were better than girders. Unfortunately I don’t think MP ever gave much thought to how to maintain them. They can be a stinker to get apart plus when you do it’s odds on you’ll find the sliders even more worn than the bushes.
I’ve only reconditioned the one set. In the end it involved making both new sliders and bushes plus having new springs wound as the only way the previous owner could dismantle them was by stretching them apart that far he could get a hacksaw to the springs and saw them in half.
It scared the whatsits off the current owner as when we lifted the front end to start work the bottom half of the front end just dropped off onto the ground.
After making new bits they were dead easy to assemble. They were like those kids “Chinese” finger cuffs. The springs wind in place easily but won’t wind off again so you’re stuck. The assembly was arranged so you couldn’t get in to wind them out.
No wonder I prefer old bikes with girder forks.

[doughobbs]

Look familiar. 1953 model.

Do you have the exhaust/muffler still ?

Hiya,
I have a muffler for it but it's a tiny bore, I suspect its for something like a 97cc engine, there is a collar screwed onto the barrel and that's it unfortunately.


I'll get some better images of frame numbers a soon as I can, thanks everyone for helping me, I really didn't know if I'd get any responses and the info so far is great!


Can anyone provide info (even just rough) on how many of these there are still in existence and any Sun owners club? I'm very new to the world of vintage bike ownership and am still to start on the rebuild path, I have a rusty VW bus on my driveway to finish rebuilding first

[Rex]

Don't know if there's a Sun owners club, but there's very likely some Sun literature and a marque specialist in the VMCC.

[33d6]

Be very careful with that muffler. The outlet pipe should have a much smaller diameter than the front header pipe.
I would expect it to be about 60-62% of the front pipe coming out of the cylinder. Quite small in fact. James used the same tail pipe on their 197 Captain as they did on their 98cc Comet.
The standard mistake four stroke owners make is to increase the diameter of the tailpipe to the same diameter as the front pipe.
Getting a two stroke exhaust right is a lot more subtle than you think, especially for a road bike where you have to keep the noise down as well.
You don’t really need much special Sun literature. The standard Villiers literature will cover your complete power unit including ignition and carb plus all the lighting. The VMCC library has some early MP fork info. There isn’t much around. MP weren’t great on maintenance manuals. I suspect the wheels and hubs are common British Hub Co stuff so basically the same as James, Francis Barnett and Norman of the period. The only stuff unique to Sun is the frame, rear suspension, tank and paint job. Otherwise it just another variation of the common Villiers lightweight of the period.
It’s like having a rose garden. They might all be different colours and have different perfumes but all come from a common stock and the care of them is much the same. Villiers powered bikes might come in different makes but like the roses care and maintenance for one is much like any other.
The name on the tank really doesn’t make much difference.

[doughobbs]

Be very careful with that muffler. The outlet pipe should have a much smaller diameter than the front header pipe.
I would expect it to be about 60-62% of the front pipe coming out of the cylinder. Quite small in fact.

The muffler I have isn't for this bike, as said its tiny, something more like a 100cc engine not a 200cc, there is no chance I'd even try and make it fit.

[doughobbs]

I've tried to get some better shots of those numbers on the bottom of the seat tube - these are not stampings but raised numbers (like the swing arm could they be casting numbers?) - short of removing the engine and also totally paint-stripping the frame I'm not sure I can get any better images than these (I have a VW bus on the go at the moment so the SUN is not getting pulled apart for some time hehe!).

The numbers to me read S15(splat)2 - would you agree?

[Rex]

As a  rule every raised number is just a casting mark, and that certainly  looks just like one of them.

[33d6]

As R says, raised numbers are for factory internal use and not much help in identifying your bike. Only the stamped numbers identify your individual bike and are the only ones authorities are interested in.
If about 1&1/4” in diameter that exhaust probably came off a 10D Villiers engine. It seems to have the standard wiggle to clear the left hand footrest. Someone will be thrilled to get it.

[doughobbs]

I finally found the frame number with the help of someone in the Villiers group on FaceBook!

As for the exhaust I found an engine it goes with too - looks like its a 1F engine I (again from people on the Villiers FB group)