scootz
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posted on 12/7/10 at 06:32 PM |
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Measured the Quaife box at 20cm... shouldn't shove things out of proportion too much!
It's Evolution Baby!
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scootz
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posted on 12/7/10 at 07:51 PM |
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Hurrah... and now I have one! BMW shaft drive here I come!
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Suzuki B-king rear-end for sale!
It's Evolution Baby!
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scootz
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posted on 15/7/10 at 05:16 PM |
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Hmmm... now wondering if I should just go the whole BMW-hog and get a boxer twin engine!!!
Would be going from 140bhp to 110bhp, but it kind of makes sense! The engines less tall, so lowers the COG.
Any opinions?
Do the BMW Boxer engines respond well to tuning mods?
Are they super heavy (with gearbox)?
All inputs gratefully received!
It's Evolution Baby!
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smart51
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posted on 15/7/10 at 05:37 PM |
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quote: Originally posted by scootz
The engines less tall, so lowers the COG.
Which is a good thing, especially at the rear where the effective track is narrow. On the other hand, if it is a much heavier engine, it will pull
the centre of gravity backwards, negating all the gains in lowering it. Find out what one weighs first.
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scootz
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posted on 15/7/10 at 06:28 PM |
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I've been looking all afternoon to see what a 'typical' BMW boxer engine weighs without success!
I'll keep plugging away!
Mind you, the gearbox on the Beemer lumps does stick out of the block a bit... pushes the swing-arm further back!
It's Evolution Baby!
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JF
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posted on 15/7/10 at 09:50 PM |
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Well I don't think it will be that much heavier the say the Aprillia engine. Seeing that the RSV Mille and the BWM R1200S only differ about 2kg
in total weight.
You might lose a some horses, but did you look at the torque gain? Especially the R1200RT has a really well pulling engine. Doing 120NM at 6000rpm
against the 101NM at 7250rpm for the aprillia.
Even though your trike will be really light for a car, it will still be quite heavy for a bike. I think those extra NM will make it quicker.
Be aware of the BMW gearboxes though. There have been really lousy series with high repair costs.
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scootz
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posted on 15/7/10 at 09:56 PM |
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Thanks for that... I'm giving it serious thought - just trying to find out as much as I can about the BMW units.
Not many for sale just now though... I've U2U's Mal to see if he can help!
It's Evolution Baby!
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scootz
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posted on 16/7/10 at 09:30 AM |
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Definitely morphing into a BMW-thingy! Found a company who is building 'normal' trikes using brand new R1200C's and they have lots of
rear-end bits and other 'stuff' going spare.
I dread to think what this little lot would have cost if I went straight to Mr BMW!
SWINGARM ASSY
Image deleted by owner
REAR CALIPER ASSY
Image deleted by owner
Image deleted by owner
SHOCK ABSORBERS
I bought three of these as they were ridiculously cheap for new parts! I'll fiddle with spring rates and use one at the back and one on either
front corner.
WHEELS
I bought 2 of the R1200C's rear wheels (5.5" rims) to put on the front of my trike. I think they look really nice! I'll just use the
bike tyres that come with them to get it through MSVA, etc. then switch over to car tyres. I'll have a custom 'fat' wheel made for the
back.
Image deleted by owner
FRONT CALIPERS
I've always wanted to use bike calipers on something other than a 'bike'. I'm hoping to keep weight under 300kg, so here's
my chance! Two of the BMW's calipers...
[img][/img]
It's Evolution Baby!
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iank
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posted on 16/7/10 at 10:02 AM |
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Nice, what are you using for a handbrake? Wilwood spot caliper?
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
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scootz
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posted on 16/7/10 at 10:03 AM |
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Probably the Hi-Spec one Ian...
I've had both before and I'd say the Hi Spec variant is worth the extra £20 or so.
It's Evolution Baby!
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kipper
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posted on 16/7/10 at 10:25 AM |
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hand brake
Hi guys.
on my three wheeler I have used four pot Hispec callipers with the hand brake built in on the two front wheels.
I did try to get a Suzuki Burgman rear calliper, which has a hand brake, to fit the Piaggio scooter rear end I am using but there just was'nt
enough room.
Suzuki calliper for sale if interested.
Regards Kipper.......AKA Denis.
Where did that go?
<<<<
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scootz
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posted on 16/7/10 at 10:38 AM |
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I'd thought about doing something similar, but the rear spot caliper should be an easier fit.
It's Evolution Baby!
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scootz
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posted on 16/7/10 at 05:22 PM |
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quote: Originally posted by JF
Well I don't think it will be that much heavier the say the Aprillia engine. Seeing that the RSV Mille and the BWM R1200S only differ about 2kg
in total weight.
You might lose a some horses, but did you look at the torque gain? Especially the R1200RT has a really well pulling engine. Doing 120NM at 6000rpm
against the 101NM at 7250rpm for the aprillia.
Even though your trike will be really light for a car, it will still be quite heavy for a bike. I think those extra NM will make it quicker.
Be aware of the BMW gearboxes though. There have been really lousy series with high repair costs.
Thanks for that... am I not right in thinking that the weight difference is a bit more than 2kg? I make it a difference of 49kg!
RSVR
180kg
172mph
143bhp
76ft/lbs
R1200RT
229kg
135mph
110bhp
85 ft/lbs
I'm still thinking that the RSVR engine will shove it along the road quicker, but remain open to suggestion...
It's Evolution Baby!
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JF
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posted on 16/7/10 at 11:00 PM |
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No the RT is quite a bit heavier indeed. But I compared the BWM R1200S to the Aprillia. As they are quite similar bikes.
Comparing a mille to a R1200RT is like comparing a seven to your average car.
But since those two bikes are very similar in weight, I suspect the engines might very well be quite similiar in weight. And the R1200 engines are
basically all the same.
But I think a R1200RT egine would suit your trike better then an R1200S.
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scootz
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posted on 17/7/10 at 09:08 AM |
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Ah, yes...
I... must... learn... to... read... posts... properly!
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I... must... learn... to... read... posts... properly!
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I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
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I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
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I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
I... must... learn... to... read... posts... properly!
It's Evolution Baby!
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scootz
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posted on 18/7/10 at 01:48 PM |
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Right... the swingarm is manufactured to the correct offset for the bike (what were they thinking! )
The sprocket on the RSV engine is located pretty far across to the offside of the frame... not a problem as I intend to run a wide back wheel and will
have one made (probably Image) to suit whatever rear-wheel centre-line I require.
This increased offset also has the benefit of bringing the swingarm tighter to the offside frame making the mounting to the spindle pick-up point
straightforward.
However...
I now have a fairly wide gap to be 'bridged' between the nearside spindle pick-up point and the swingarm.
How best to deal with this?
I'm just conscious of the need to keep the back end as strong and as solid as possible.
All suggestions welcomed!
Hope this diagram helps a bit...
[img][/img]
It's Evolution Baby!
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scootz
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posted on 18/7/10 at 05:50 PM |
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Interesting development!!!
I've been offered a full BMW K1200RS bike at a very reasonable price! That would make things a zillion times easier (albeit a zillion times
less interesting!).
Oooooooh... I'm all confuzzled! Means the Aprilia engine, and a couple of the BMW bits I've bought would become redundant, but hey... I
like selling things!
It's Evolution Baby!
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scootz
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posted on 18/7/10 at 08:46 PM |
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Decision made... K1200RS running gear it is! And... shock-horror... NO REVERSE!
Been here a million times before... things get waaaaaay over-ambitious and the project falls flat on its face!
The K1200RS has lots of hard fastening points on it's cast-ali frame, so I'm thinking sub-frame...
Saw this project (Shrike)... gives an idea of where I'm going with the union between bike and single-seater. Unlikely to keep the tank in
it's original position due to concerns over COG, and would probably remove the tail subframe.
More pics LINKY
[Edited on 19/7/10 by scootz]
It's Evolution Baby!
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iank
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posted on 18/7/10 at 09:36 PM |
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kb58 knows the engineer who made the shrike.
http://www.locostbuilders.co.uk/viewthread.php?tid=21777
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
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scootz
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posted on 19/7/10 at 07:38 AM |
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I've dropped him (Shrike builder) an email to see if he has any of the drawings for his 'headstock to chassis' mounts... could save
me a LOT of time!
It's Evolution Baby!
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zilspeed
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posted on 19/7/10 at 10:38 AM |
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The K is a fair call IMHO, especially if you get swinging arm etc all as one package.
The boxer would not have gone well with the single seater chassis.
Grinnall Scorpion should provide many valid reference points as to how to proceed, seeing as that's a K powered reverse trike.
P.S. Got your previous email, was just chewing over how to suggest a K rather than a boxer.
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scootz
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posted on 19/7/10 at 12:09 PM |
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Did you have a peak at the Shrike link Zil? What did you think of using the bikes chassis as a subframe (particularly the mounting the headstock to
the single seater chassis idea)?
It's Evolution Baby!
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zilspeed
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posted on 19/7/10 at 12:53 PM |
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quote: Originally posted by scootz
Did you have a peak at the Shrike link Zil? What did you think of using the bikes chassis as a subframe (particularly the mounting the headstock to
the single seater chassis idea)?
Well, it's all down to packaging really isn't it.
If you look at the back of any of the bike engined single seaters, they have way less space between the front of the engine and the buklhead behind
the driver. Most have side exit exhausts too and it all helps to foreshorten the overall wheelbase.
It might be relatively simple to put the car and bike together like this, but it's far from the best solution in this regards.
You really want the engine to be pushed forward as much as you can so that you can keep the wheelbase managable. Having the top yoke still in place
kills this stone dead.
As ever, I think the best way forward is to put the engine exactly where you want it then fabricate to the other known structure - the car chassis.
Keeping the bike frame might be easier, but it's not best, IMHO.
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scootz
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posted on 19/7/10 at 01:00 PM |
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Good points Zil... and very well made!
I really want as much weight as low-down in the chassis as I can get it.
The flat nature of the in-line four K engine probably makes the fabrication of engine mounts a tad easier.
I'll give you a shout once the bike has arrived (probably next week) and I have it stripped!
It's Evolution Baby!
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smart51
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posted on 19/7/10 at 01:06 PM |
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mounting the bike frame to the car frame is a nice simple idea but I would be concerned about weight. Bike frames are designed to support a whole lot
of load through the yoke that would be better distributed about a space frame. This strength over a small yoke length means a substantial structure.
They also are not designed for a lot of lateral force (bikes lean). If it makes the build simple then I don't see why you shouldn't do it
this way though. What would your wheelbase be if you made your car this way? I'd start to scratch my head a bit if it got much more than say
2.5m long. Mine will have a 2.4m wheelbase versus a 1.3m track (tyre centres) which is on the long side of the 1.6:1 rule of thumb. Longer than 1.6
and the car's handling is biased more in favour of straight line stability than cornering nimbleness. Get it too long and it will turn like a
tanker. Too short and it will be twitchy.
[Edited on 19-7-2010 by smart51]
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