Rudge top end rebuild
- Yorick
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Re: Rudge top end rebuild
I had a similar effect with a 1931 Sunbeam I rebuilt a couple of years ago. It came to me having been rebored but it turned out to have been done without enough clearance so it tightened up after a few miles if I used anything like full throttle. My piston wasn't too bad and the rings were OK so I just cleaned it up with a very fine file and had a couple of thou honed out of the barrel. Fine after that.
Nice looking Rudge - radial 4 valve? (<edit> yes of course now I look at the later photos</edit>) Mind you I prefer my carpet to yours!
My 'beam:
Nice looking Rudge - radial 4 valve? (<edit> yes of course now I look at the later photos</edit>) Mind you I prefer my carpet to yours!
My 'beam:
Ian.
1952 Norton ES2
1955 Francis Barnett Cruiser 75.
1952 Norton ES2
1955 Francis Barnett Cruiser 75.
- Tricky
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Re: Rudge top end rebuild
That's an awful of blow-by there even for an oldie- has obviously not been sealing well for a good whileHarry wrote: ↑Sun Mar 29, 2020 4:31 pm Part of the problem was my own doing, I'd been racing a bloke on a Bonneville and had been on a long flat road, running with the throttle on the stop for a good few miles and eventually I felt it start to lose power and then it nipped up just as I coasted in.
I knew it was shagged anyway, so I'd lost any mechanical sympathy anyway, but after it had cooled down it got me back to the camp site.
This was a the result though...
IMG_0715 by Iccy, on Flickr
One broken ring and clear evidence of a seizure.
IMG_0711 by Iccy, on Flickr
P.S. Love the thread
- Yorick
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Re: Rudge top end rebuild
Not only four valves, but arranged radially and not just two lines of two.
Re: Rudge top end rebuild
There’s a Like for the thread.
There was a fella on the other Forum who had a Rudge. He also had an Lc that was having a full nut and bolt rebuild. Don’t know what happened to that , he never told us.
Hope all goes well with this one.
There was a fella on the other Forum who had a Rudge. He also had an Lc that was having a full nut and bolt rebuild. Don’t know what happened to that , he never told us.
Hope all goes well with this one.
- Rockburner
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Re: Rudge top end rebuild
Just looking at it, and comparing it with the head I'd say that's correct - it looks like it would give a pretty high compression ratio. Normal road going bikes of the time (Rudge might be a bit different) were lucky to get more than 7 - 8 compression ratio on standard designs. That big dome looks like a hi-comp idea.Harry wrote: ↑Mon Mar 30, 2020 4:40 am
The piston in mine is taken from a drawing that (I think) someone did in the 60's, someone in the club got hold of it, assumed it was the right one and had a batch made - but there is a lot of discussion to say that it isn't a great design and was done by a racer back in the day that wanted a specific application for his machine, so it's not the best design as a standard piston.
Can't tell from the photos - but is it a Rudge badged engine - or a JAP? It kinda looks like a twin-port JAP from some angles (My Dad's HRD-Vincent is (iirc) a twin port JAP - he normally runs it on just 1 port though - says it runs better).
non quod, sed quomodo
- Dodgy69
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Re: Rudge top end rebuild
If you're get it running anything like the 30s Rudge in the Barry Sheene memorial video, you'll have done a good job.
Yamaha rocket 3
Re: Rudge top end rebuild
It’s amazing you can still keep them running if the factory closed so long ago, impressiveHarry wrote: ↑Mon Mar 30, 2020 4:40 amYes and no.
The club does commission parts such as pistons and things, and you can get some consumable parts, but often the knowledge to replicate original stuff just isn't there and drawings of the day (if they exist) are not accurate. The Rudge factory were never really in the money and quite often just used whatever was on the shelf, so two bikes leaving the factory on the same day might be different. The factory closed it's doors in 1939 and never made another bike.
There were lots of new things coming out back in the 1930's and from what I know it appears that they didn't always update drawings, or they did but the updated version got lost and then aftermarket post-production parts were made using the originals, which might be wrong.
The piston in mine is taken from a drawing that (I think) someone did in the 60's, someone in the club got hold of it, assumed it was the right one and had a batch made - but there is a lot of discussion to say that it isn't a great design and was done by a racer back in the day that wanted a specific application for his machine, so it's not the best design as a standard piston.
I think people mean well but there is a terrible amount of politics in the club, there are a lot of bitter rivalries going back decades, especially around parts, as soon as one faction has some parts made the other decries them as not suitable or not to original design, etc.
To be honest it's tiring, but that's classic bike clubs for you.
Crankcases, barrels, cylinder heads, etc, are difficult to come by.
I bought a lathe just to make bits for this bike.
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Re: Rudge top end rebuild
Your Rudge is the only bike on this or the other forum that I genuinely would love to own. I couldn't own one as I'm a mechanical numpty and have no idea how old bikes work (or new ones really but you rarely need to know with them), but as a 'Thing' it's so captivating. For me I think there is something about 30's bikes and cars that I just find really attractive.
Do keep posting about it, as it's an amazing bike.
Do keep posting about it, as it's an amazing bike.
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Re: Rudge top end rebuild
What that club needs is an alpha male in charge of it.Harry wrote:I think people mean well but there is a terrible amount of politics in the club, there are a lot of bitter rivalries going back decades, especially around parts, as soon as one faction has some parts made the other decries them as not suitable or not to original design, etc.
To be honest it's tiring, but that's classic bike clubs for you.
I take my disaster-hit pistons, etc., to work and amaze my old-bike owning colleagues.
- Rockburner
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Re: Rudge top end rebuild
I think that's the defining description of classic bike ownership.
non quod, sed quomodo
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Re: Rudge top end rebuild
Yeah well what does a routine service on a Ducati cost?Harry wrote:It's a good job I really love this bike, it needs a lot of attention and it eats money.
- Noggin
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Re: Rudge top end rebuild
Totally love this bike. I dream of having a garage and the ability to look after something like it
Looking forward to more photos!!
Looking forward to more photos!!
Life is for living. Buy the shoes. Eat the cake. Ride the bikes. Just, ride the bikes!!
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Re: Rudge top end rebuild
The thing about these old bikes (my oldest is 'only' 1965) is that they take a lot of looking after, but it's all pretty simple.
You really can do 99% of stuff yourself with not that many tools.
You really can do 99% of stuff yourself with not that many tools.
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Re: Rudge top end rebuild
Same with mine....the le club make lots of bits, and the stuff is usually simple...though i hope the motor on the viceroy doesnt go bang. I also have ( i think) a clutch problem that might get mucky.
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Re: Rudge top end rebuild
I expect the sort of eccentric who rides a Rudge usually owns a small lathe and even some reamers.
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Re: Rudge top end rebuild
This is true of my Kawasaki (1982 Z1000J based), the engine is very simple, and if it does need any machining work done there's people who can do it, from the mid 80s onwards bike engines improve massively from a reliability point of view, but they get a lot more complicated and the tolerances are a lot tighter, these engines seem to be a lot better if they've never been apart.Mr. Dazzle wrote: ↑Wed Sep 02, 2020 9:21 pm The thing about these old bikes (my oldest is 'only' 1965) is that they take a lot of looking after, but it's all pretty simple.
You really can do 99% of stuff yourself with not that many tools.
Honda Owner
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Re: Rudge top end rebuild
We inherited several bikes from my FiL, amoung them a 69 Triumph and a 98 Honda CBR.
Obviously the Honda is 30 years newer...in reality it's 50 years newer cause the Triumph was an old design even when it was new. It really shows. The Honda just needed a new battery and it started up like it was parked yesterday and runs like a sewing machine.
The Triumph needs something doing pretty much every time you touch it. It's definitely a lifestyle ownership prospect.
Obviously the Honda is 30 years newer...in reality it's 50 years newer cause the Triumph was an old design even when it was new. It really shows. The Honda just needed a new battery and it started up like it was parked yesterday and runs like a sewing machine.
The Triumph needs something doing pretty much every time you touch it. It's definitely a lifestyle ownership prospect.