Author Topic: New Project - cheap CB50 model or one off build - help me decide... (Read 3170 times)

lordmoonpie · « **on:** July 16, 2009, 04:49:30 AM »

Now the CR750 is nearing completion, I've started to think about the next big project (got 4 other 'small' projects on the go already:-))

My thoughts are split at present so I could do with some views to help me decide....
Option One
I've always loved the V1000 Britten and fancy the idea of building my own V-twin probably using some of John Britten's ideas such as the modified hossack front end and ducted cooling. The big challenge for me here is building my own engine and I'm looking at aroudn 10 years to do it.

Option Two
There's a guy here in the UK who builds mad multi cylinder bikes - he takes a standard bike and grafts engines together to make some monster cylindered technology study. That got me to thinking that if I could get a cheap accesible CB50 engine of some kind, I might be able to apply the same theories and build a 300cc six cylinder just like Mike's! Again, many years to do but I took 6 to build the CR750 so I know I have the 'vision' if you like. If I did this - what model of engine would be good to go for?

Both of the above original bikes are in my top three all time wish list bikes, the Honda six being no.1 and the Britten no.2 but which do you think I should set off on as a project? Let me have your thoguhts and I might eventually make a decision!!

bryanj · « **Reply #1 on:** July 16, 2009, 07:23:22 AM »

Got to be the six, just for the exhaust sound

bucky katt · « **Reply #2 on:** July 16, 2009, 12:06:10 PM »

hmmmmmmmmmmmmmm a 1500cc kawasaki h2x2 six

lordmoonpie · « **Reply #3 on:** July 16, 2009, 01:35:26 PM »

Wish I could remember the guy's name Fuzzy, errr sorry Bucky

He built a 27 cylinder Kawasaki H something or other for a show two years ago....if I can find a picture I'll post it - it's AWESOME!

dave400 · « **Reply #4 on:** July 16, 2009, 02:00:09 PM »

George Beale will sort you out with nice a sounding 6 for about £300K.

What a nice sound a small six makes!

mcpuffett · « **Reply #5 on:** July 16, 2009, 02:51:19 PM »

Your thinking of Allan Millyard me thinks

Sam Green Racing · « **Reply #6 on:** July 16, 2009, 03:04:03 PM »

me thinks you is right.

Sam.

malcolmgb · « **Reply #7 on:** July 16, 2009, 03:25:51 PM »

OK, there was a V8 500 Yamaha engine at Stafford show a couple of years ago, not seen it since, based on 2 - 250cc 4 cylinder engines.
At Mallory on Sunday I was talking to a guy who had 3 65cc Garelli cylinders on a home made crankcase and the rear half cut off a Yamaha case for the gearbox. A very tidy machine and all road legal, he was a bit down, he fell off it going into Gerrards and damaged what he thought was a very rare headlight shell.

mlinder · « **Reply #8 on:** July 16, 2009, 03:41:31 PM »

I'd build a longitudinal 700cc V8 from a couple of cb350f's....

lordmoonpie · « **Reply #9 on:** July 17, 2009, 04:21:15 AM »

My old race mate's uncle is well on with building a 500cc V8 from two CB250RR engines. it's pretty much there bottom end but he's struggling to get a setup to fit the carbs in!

lordmoonpie · « **Reply #10 on:** July 17, 2009, 04:25:18 AM »

Quote from: mcpuffett on July 16, 2009, 02:51:19 PM

Your thinking of Allan Millyard me thinks

That's the man - I can only find pictures of his V12 kawasaki but there was a 27 cylinder monster at Stafford 2 years back...

mcpuffett · « **Reply #11 on:** July 17, 2009, 12:37:30 PM »

What about the 48 cylinder Kh

lordmoonpie · « **Reply #12 on:** July 17, 2009, 02:12:21 PM »

Nice one Mick - that's the one I was thinking of....bet that gets a bit warm sat at the lights

CBJoe · « **Reply #13 on:** July 17, 2009, 02:47:44 PM »

I want to see a video of him actually driving and cornering that monster

lordmoonpie · « **Reply #14 on:** July 18, 2009, 02:46:57 AM »

Not that I've made any decisions yet but I sent off last night for one of the last George Beale Honda 6 posters - a full poster of the replia he built, all broken down into parts - bit like the cycle world picture of the CR750 kit....now that should give me something to think about!

andy750 · « **Reply #15 on:** July 18, 2009, 03:36:53 AM »

Quote from: CBJoe on July 17, 2009, 02:47:44 PM

I want to see a video of him actually driving and cornering that monster

I couldnt resist looking....

and

malcolmgb · « **Reply #16 on:** July 18, 2009, 07:44:56 AM »

Beat me to it Andy I knew I had seen it. I still wonder if they are all running cylinders or if some are just for show but a great build.

lordmoonpie · « **Reply #17 on:** July 23, 2009, 03:51:05 AM »

Having done some more research I might be heading down the V-twin route. Apparently the honda six uses a crank that is pressed from loads of tiny parts not much bigger than a domino. It's so small that you can deform and ruin the crank by hand if you don't look after it properly. The guy who built the replicas said making it was like trying to balance 14 billiard balls on top of each other to make a tower! Oh and with the lack of flywheel effect it's possible with a tiny twist of the throttle to send the revs from 1000 to 20,000 rpm and destroy the lot!

Sounds a *little* bit too difficult for my home workshop

KB02 · « **Reply #18 on:** July 23, 2009, 04:54:15 AM »

Quote from: andy750 on July 18, 2009, 03:36:53 AM

That thing must have incredible throttle lag, If you listen to it rev, and then just imagine the power it takes to get that sucker to spin up...

...still wouldn't mind taking it out for a ride...

I say go the V-Twin route. I love my V-Twin engine.

malcolmgb · « **Reply #19 on:** July 24, 2009, 03:54:22 PM »

Just come across this again http://thekneeslider.com/archives/2008/05/30/honda-125cc-inline-4-cylinder-monkey-bike/ not sure if this is what set you off originally. Now off into the realms of fantasy, perhaps a V4 with a water jacket around the barrels and heads.

crazypj · « **Reply #20 on:** July 25, 2009, 03:54:05 PM »

Quote from: lordmoonpie on July 23, 2009, 03:51:05 AM

Having done some more research I might be heading down the V-twin route. Apparently the honda six uses a crank that is pressed from loads of tiny parts not much bigger than a domino. It's so small that you can deform and ruin the crank by hand if you don't look after it properly. The guy who built the replicas said making it was like trying to balance 14 billiard balls on top of each other to make a tower! Oh and with the lack of flywheel effect it's possible with a tiny twist of the throttle to send the revs from 1000 to 20,000 rpm and destroy the lot!

Sounds a *little* bit too difficult for my home workshop

Cylinders and crank are the easy bit, the head is where things get 'difficult'
Could make crank a bit more substantial so it wouldn't deform so easy, machine all the flywheels at same time, and make them full circle, build it into a CB400 f case ( would have 2 mains 'missing') etc
Hey, I got a dead cb350 case, another project?

PJ

lordmoonpie · « **Reply #21 on:** July 27, 2009, 11:43:14 AM »

Quote from: malcolmgb on July 24, 2009, 03:54:22 PM

Just come across this again http://thekneeslider.com/archives/2008/05/30/honda-125cc-inline-4-cylinder-monkey-bike/ not sure if this is what set you off originally. Now off into the realms of fantasy, perhaps a V4 with a water jacket around the barrels and heads.

Malcolm- that bike is Monkey Nuts!

Now I'd love to see how they built that sucker - it's a beautiful bit of kit!

Caminokid · « **Reply #22 on:** July 29, 2009, 05:30:49 AM »

Quote from: CBJoe on July 17, 2009, 02:47:44 PM

I want to see a video of him actually driving and cornering that monster

I would like to see anyone doing the same. Can you imagine dropping that thing...whether it was on the road or at a light?

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Author Topic: New Project - cheap CB50 model or one off build - help me decide... (Read 3170 times)