BMW k1200rs or other bike engines

How to upgrade your Austin...and further......
Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

gazza82 wrote:On fleabay now ...
Tl1000r motor with loom, ecu, injectors etc...
Just 2-cylinders and 996cc - well that would certainly be different... :whistle:

But you'd be in good company. Back in 1955, Ferrari experimented with an inline 2-cylinder engine with rather more displacement of 2493cc coded Tipo 116. But it kept breaking crankshafts so was abandoned.
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Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

Basil Fawlty wrote: Don't mention the output shaft is off centre. I mentioned it once but I think I got away with it all right.
... :rol:
Question for Basil and other small engine mongers. What are you trying to achieve :?: ... :wave:
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Hurtzberg
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Re: BMW k1200rs or other bike engines

Post by Hurtzberg »

Hello BD,

I would like a faster A35.

Midget engines are increasingly expensive.

A midget engine costs between £450 and £600. A rebuild to "ok" spec costs maybe another £600. Good spec costs more. Exhaust + Manifold = 440. Inlet + SU = 150 (more for rebuilt). Rolling road time is perhaps £200. Good Dizzy £200 etc
So easily £2000.

Rover K series is a common moggy/midget upgrade but you hear horror stories. It also requires a ford Type 9 gearbox and adapter plate or bell housing. This is heavy and not cheap. I would be tempted by this. I believe someone (Andy?) has done this conversion. Would love to know from him how hard it is.

Sigma. Probably more fabrication than K series as only BD has walked this path. BD said the exhaust manifold was a PITA. Still needs heavy/expensive type9 gearbox.

Bike engine and box. Unknown difficulty. Possibly prop alignment issues. Potentially most likely to break gearbox/clutch out of the above options. The fun high revving nature could get tiresome quickly if it is used for more than a backroad/track toy. This is of most interest to me at the moment as I still have the option of liberating a honda blackbird engine from hibernation.

Having typed that out, I come to the depressing realisation that I should probably just be happy with my 948 until I'm older, richer and have spare time again :barr:

I also realise that I should have bought an already 1275 and disc brake equipped A35 to start with!


Summary: I don't care if the engine is big, small or medium, what I am trying to achieve is a reasonably fast A35 for as little money as possible.
Andrew

1957 A35
Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

Hurtzberg wrote:I would like a faster A35.
Excellent with full marks for your tenacity and enthusiasm... :thumbs:
Hurtzberg wrote:Midget engines are increasingly expensive.
Yes but still probably the cheapest option. Changing the engine type or even just the cylinder head type means installation and ancillary costs dominate, not the basic components.
Hurtzberg wrote:Sigma. Probably more fabrication than K series as only BD has walked this path. BD said the exhaust manifold was a PITA.
Fabrication required for K-series and Sigma must be very similar. Sigma 4-2-1 exhaust manifold was a real challenge which is beyond me but thankfully within my son's capability. But we have done the difficult bit and have the jig so next one will be much easier... :mrgreen:
Hurtzberg wrote:Still needs heavy/expensive type9 gearbox.
Type 9 gets lighter with Quaife alloy case. Second-hand Type 9 boxes were available for around £150 when I last looked, but are probably worth more now. Peanuts compared to minimum cost competition boxes which start at £2000 with sky as the limit.
Hurtzberg wrote:Bike engine and box. Unknown difficulty. Possibly prop alignment issues. Potentially most likely to break gearbox/clutch out of the above options. The fun high revving nature could get tiresome quickly if it is used for more than a backroad/track toy. This is of most interest to me at the moment as I still have the option of liberating a honda blackbird engine from hibernation.
Good summation - fragile transmission, engine with limited life (in a car) and narrow torque band which is a nightmare on the road and can even be difficult on the track.
Hurtzberg wrote:Summary: I don't care if the engine is big, small or medium, what I am trying to achieve is a reasonably fast A35 for as little money as possible.
1275 A-series in moderate state of tune sounds just right. We are looking towards Duratec next... :thumbs:
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Chris T
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Re: BMW k1200rs or other bike engines

Post by Chris T »

Hurtzberg wrote:what I am trying to achieve is a reasonably fast A35 for as little money as possible.

A 1275 in any state of tune (or 1098 for that matter) will satisfy this. Straight swap. Forget the rebuild & performance upgrades until time & finances permit. Just drop it in & tweak on the hoof. Only a day of downtime required.
Chris T.
400,000+ A30 miles in 40 years
Austins <=> sustAin
Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

Chris T wrote:A 1275 in any state of tune ... will satisfy this. Straight swap. Forget the rebuild & performance upgrades until time & finances permit. Just drop it in & tweak on the hoof. Only a day of downtime required.
Chris T.
:iagree:
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Re: BMW k1200rs or other bike engines

Post by gazza82 »

the option to hunting for Midget engine is a 1275 Marina .. admittedly these are starting to rise in proce due to the Academy boys and there are mods needed to mate to a Midget box.

What about alternatives to Type 9s? CBs using a Toyota T50 box and 6-speed Toyota/Lexus are starting to appear on the market .. problem is in-line boxes are either old and need work or very new and very expensive! The box in my BRZ looks long but hasn't got a large bell housing (but it is an auto!). They also fit them to GT86s, come in manual form and the cars do get written-off .. !

I know someone putting a Mazda TwinCam and box in a Midget. Lots of work on the gearbox tunnel but the Midget gearbox is enclosed unlike the A35 which is open underneath.


Think outside the box .. ??
"If you're driving on the edge ... you're leaving too much room!"

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Cars: "Project 757" '59 A35 2-door bought in 1971 & Subaru BRZ SE LUX Auto plus "family fleet": Alfa MiTo, Peugeot 206, (Ex '98 Alfa Romeo 156 2.0 TS)
Hurtzberg
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Re: BMW k1200rs or other bike engines

Post by Hurtzberg »

Thanks Chris, BD and Gazza.

The mx5 always seems to be overlooked. I had the 1.8s mk1 which is around 135hp and pretty rubbish mpg. It can be turbo'd or supercharged too.

A rotten mk2 (as Mk1s are getting sort after) Could be a very cheap way of getting an engine and box.

Alternative gearbox for old fast fords is the RX8 gearbox. I understand it is rather wide so probably not suitable for us.
Andrew

1957 A35
Dave Clark
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Re: BMW k1200rs or other bike engines

Post by Dave Clark »

Any MX5 engine and box would be a big upgrade, even a 1.6

Buy a rusty but running MX5 for less than £500 and you have a complete package, including fuel injection.

Most MX5 engines are unburstable and parts are cheap and available
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Re: BMW k1200rs or other bike engines

Post by Hurtzberg »

Hi Dave,

When people mentioned MX5 in the past, a rumour came up that it had been tried and was either too long or too tall.

I believe you have a Mx5. Next time you're working on it,can you grab some rough measurements to see how tight a fit it'll be?

Thanks, Andrew.
Andrew

1957 A35
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gazza82
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Re: BMW k1200rs or other bike engines

Post by gazza82 »

It was definitely too tall for a Midget bonnet .. it was getting a large "power bulge" ..
"If you're driving on the edge ... you're leaving too much room!"

Club WebEditor.

Cars: "Project 757" '59 A35 2-door bought in 1971 & Subaru BRZ SE LUX Auto plus "family fleet": Alfa MiTo, Peugeot 206, (Ex '98 Alfa Romeo 156 2.0 TS)
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Countryboy
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Re: BMW k1200rs or other bike engines

Post by Countryboy »

Given the A Series is lost height wise , I cannot believe it wouldn't fit :study:

I think a supercharged MX5 1.8 with a 6 speed box would compliment my 2002 nicely :thumbs:
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ian24ian
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Re: BMW k1200rs or other bike engines

Post by ian24ian »

Toyota 4age 1600 is a compact engine, fits quite well in rwd format, often thought about suzuki cappuccino, 3 cylinder turbo engine, but I believe they are pricey to tune,
Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

Just a note of caution. Mazda B-engine as fitted to MX5 1.6 and 1.8 has an iron block. So does the Toyota 4age. A35 weight distribution is already compromised by heavy A-series. I would hesitate to fit anything much heavier :!:

Mazda L-engine as used by MX5 2.0L has alloy block and has common design with Ford Duratec. Suspect this 2.0L engine is lighter than smaller Mazda B-engine and possibly A-series.

Worth checking engine weight before making any decisions... :whistle:
Last edited by Big Daddy on Wed Mar 15, 2017 11:44 pm, edited 1 time in total.
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Big Daddy
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Re: BMW k1200rs or other bike engines

Post by Big Daddy »

Hurtzberg wrote:Alternative gearbox for old fast fords is the RX8 gearbox. I understand it is rather wide so probably not suitable for us.
Question for Mazda enthusiasts... :wave:

What's the difference between MX5 and RX8 gearboxes for both 5-speed and 6-speed variants :?:
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