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Technical Discussion Forum / Tank gear gate
« Last post by singleminded on October 20, 2018, 05:55:37 PM »
I've been having a go at making a later type 4 speed gear gate..Vic kindly lent me the gate to copy, and it's been a lot of fun :-\..
Her's what I came up with..The one on the tank was my first try and 4 later I have a working prototype.
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Technical Discussion Forum / 1932 clutch plate
« Last post by singleminded on October 20, 2018, 05:52:21 PM »
Just and update..I managed to get a clutch pressure plate that had been messed about with.
My pressure plate got damaged by the release bearing and was useless, so I found one way to repair it.
I machined the bearing dome off, or at least the remnants of the dome, and opened the hole as large as possible without cutting into the spring cup holes. Then I found a piece of 1/2 steel plate and turned it to fit inside the pressure plate and poke through the hole i had machined, the plate was then brazed in place.
the plate was mounted in the 4 jaw chuck and centered on the outer diameter of the plate and the bearing hole was bored to the size of the thrust bearing.
I have had this on the bike for a test and all seems to be ok.
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Technical Discussion Forum / Re: 1935 Model 8. Is timing 9/16" or 7/16"?
« Last post by kbryt on October 18, 2018, 06:04:52 PM »
7/16  will be fine and not break your ankle like 9/16 would.

Most old road going singles will be quite happy at 1/2 or less, on full advance
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Technical Discussion Forum / 1935 Model 8. Is timing 9/16" or 7/16"?
« Last post by Exstress on October 17, 2018, 10:06:48 PM »
Hello,

Just wondered if my timing is correct as 2 reference books are saying 2 different things. 

1935 Model 8. Is timing 9/16" or 7/16" before TDC on full advance setting?


Thank you,  John.
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Technical Discussion Forum / Re: Clutch problems
« Last post by shorrog on October 13, 2018, 06:25:17 PM »
One other thing that may be helpful. I put together a short video of adjusting the gear box selector mechanism and that can be found athttps://www.marston-sunbeam.org/technicalNotes/Model9GearboxAdjustment.html

There are also some photos of a three speed gearbox strip down and rebuild.

Graham
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Technical Discussion Forum / Re: Clutch problems
« Last post by shorrog on October 13, 2018, 06:19:52 PM »
This was the reply that Ian helpfully put together.

Welcome to Model 9 Ownership and to joining our prestigious club , You have inherited a very desirable Motorcycle , Lucky man.

However , running the clutch with only one clutch stop operating will give unequal pressure on the outer plate and can give rise to clutch drum bearing failure and could damage the gearbox  main shaft if carried out over a long period.  The clutch stops prevent graunching into gear but you must check the main shaft sleeve gear bearing to make sure the clutch assy does not wobble about, if it does you won’t get a clean opening of the clutch and no attempt at adjustment will prevail.

If the clutch does not run true then the pushrod will foul the main shaft bore and cause excessive wear to both and be a cause of drag as both run at different speeds   

When all of the clutch components are correct including bearings the clutch will open freely and spin true without any drag at all and all bearings without wear , the clutch stops can be used with the lightest of pressure. It is best when starting off to pull the clutch lever in and COUNT TO  THREE and the gear will engage like a knife through butter, totally graunchless. This is providing that the spring pressures are equal and the plates are flat and true and the throwout ratchet adjustment is correct.

Maybe it would be best to get the clutch working properly before investigating your gear problem , The clutch stops are fitted with a hard red fibre insert , It is best to have both stops with the identical material and size otherwise the friction will differ across the clutch plate and the effect be unequal  friction .

There is a modification that is possible that avoids the clutch drag , main shaft pushrod problem, and avoids using the clutch stops altogether. But that can be for later,
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Technical Discussion Forum / Clutch problems
« Last post by shorrog on October 13, 2018, 06:18:43 PM »
I have been coipied in on the following email thread and I am posting here as other folks may find the information useful.
Graham

I have just joined the Marston club and wondered if someone might be able to help me with a couple of questions/advice. I have recently inherited my grandfather's 1931 model 9. I am a motorcyclist but have very little mechanical expertise, and am certainly all at sea with this beast of a bike! It has been running, and I have done a couple of hundred miles on it over the summer, but now there are one or two of problems.

 

Firstly, it lost the upper clutch stop. Not realising that it had an important role (!) I carried on riding the machine. Was that a bad mistake??? Over time I found it was suffering from considerable graunching when changing gear and no amount of clutch adjustment helped any. Does that figure? Could I have caused some damage without the clutch stop in place??

Also, out of interest, what would the frictionless end of the clutch stop have been made of originally?

Anyway, I now have a newly made clutch stop and will try to set the bike up. What exactly does the clutch stop do??

The other problem is that it will no longer go into 3rd gear. Does anyone have any idea as to what the problem might be? Could it be connected to the missing clutch stop?????
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Technical Discussion Forum / Re: Help and Guidance Wanted
« Last post by Rick Parkington on October 08, 2018, 07:49:16 PM »
Hi Bob,
Have to say I agree with Kbryt; except perhaps that in my opinion if making the bike into something more sporty would make it more what you want then, provided you don't lose/sell any of the bits or make any irreversible alterations, I don't see any harm in it.
To be frank if the bloke who said it was 'just a bit of paint and plating' has dropped off the radar you have probably had a lucky escape. I differentiate 'rebuilding' from 'restoring' because you can restore a bike simply by pulling it apart, sending half to platers and half to painters, bolt it back together and enter a show with  a complete pile of junk that won't run. Rebuilding is, to me at least, a more honourable task that involves finding anything that isn't working properly and fixing it. Whether the end result shines or not is down to your priorities and budget.
I have spent many hours discussing the hard life of the restorer with Chris Odling and I imagine his reluctance to get involved is simply that for a specialist, while 'unit repair' - gearboxes, carbs, magnetos whatever - can just about be viable because all are usually subject to the same predictable faults (plus the occasional horrors) enabling you to predict time/cost etc; with a complete machine not only does it take up a lot of space in your small workshop but - being a cluster of unit repairs - there is a far greater opportunity for the occasional horrors to accumulate into a nightmare.
I hope Kbryt will agree that being a pro-restorer means you either do the job to the best of your ability and, effectively, lose money or you bodge it and profit.
For example I recently machined up two clutch keys for a 3 speed gearbox from EN16T round bar. By the time I had milled and hand finished them about three hours had passed. At a modest labour rate of,  say £30 ph in today's world,  those two keys will cost you £90 plus a fiver for material, £95 the pair - does that sound like good value to you? Didn't think so - especially when, no doubt, someone else will saw them off a length of mild steel square bar and sell them on Ebay for a fiver. If you don't ride the bike much they'll be fine...
So, I have to look at them and split the difference between what they cost me in time and what 'the market will stand' to reach a figure that will hopefully not cause a seizure.
Multiply this by every one of the hundreds of jobs involved in a restoration and you can see why a restorer either has to swallow the fact that he's making a loss on every bike he builds or become known as a 'rip off merchant'. Those pro companies who charge their hourly rate whether they are rebuilding a gearbox or going to get your parts from the blasters are the devils of the old bike scene but do you know a builder who says, 'Ooh, that extension's a 30 grand job...but that's an awful lot of money...let's call it ten.' If you do give me his number!
Chris Fisher is a mate, a Sunbeam owner and a very good guy but it sounds like you need local help and he's as far away as you can go without getting wet feet so I think your VMCC mates are your best bet. Sure you can get crap advice from VMCC members, as you can from web forums, but there are a lot of clever people in the VMCC too and I know from living in Scotland that it's a pretty close network up there. Your friends who suggested you 'project manage' are spot on; the worst you can do is give the whole bike to someone and say 'call me when its ready' for the reasons above, it will be either too many years or too many pounds. Break the job into chunks and I'm sure Chris (O not F) will be happy to take them on.
Finally, is it really worth going down the restoration route? Especially with an un-restored bike, I'm a great believer in doing a crap paint job on replacement parts (brush on satin 'no primer needed' garden gate enamel from DIY stores) to blend in with the rest and as Kbryt says, the un-restored look is more popular nowadays, so why spend a load of cash restoring the bike to match a new mudguard when you can paint the new mudguard to match the rest?   
Cheers Rick

 
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Beamers General Discussion Forum / Heads up sunbeam engine on auction not ebay
« Last post by kbryt on October 07, 2018, 07:14:22 PM »
Richard Edmonds auctions Chippenham Oct 18 lot 280

also a couple 'Beam flat fuel tanks.



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Technical Discussion Forum / Re: Kickstart rubber
« Last post by VicYouel on October 07, 2018, 09:33:26 AM »
See earlier thread at https://www.marston-sunbeam.org/sunbeamForum/index.php?topic=229.0   or suppliers list on the club web site..... Geoff Hunter. It is possible we may stock these in future in our club shop as it is difficult for many members to make contact with specialists who do not use the internnet.
Vic
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