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How quick would a BEC trike be compared to 4 wheel BEC?
mr henderson - 6/1/09 at 12:14 PM

Take for instance, the Grinall Scorpion style of trike, basically the front 2 wheels in a standard car layout mated to the back half of a motorbike.

It would seem that the trike layout would save quite a bit of weight, plus the power transmission would be optimal, as opposed to having to go through a crownwheel and pinion, and various CV and UJs

Less rubber on the road with the trike, so maybe traction would be less, but the weight saving might make up for that.

How about cornering, though?

Anyway, I would, as always, be very interested to hear your thoughts on this question

John

Triton - 6/1/09 at 12:26 PM

Complete giggle fest of black lines everywhere you go oh and won't fall off the back when you crack the throttle open....

cd.thomson - 6/1/09 at 12:28 PM

Have you considered a two wheel BEC John, even better weight saving. Cornering would be okay, could probably use a handlebar arrangement and weight distribution.

mr henderson - 6/1/09 at 12:36 PM

quote:
Originally posted by cd.thomson
Have you considered a two wheel BEC John, even better weight saving. Cornering would be okay, could probably use a handlebar arrangement and weight distribution.


Too dangerous. I'm thinking about a vehicle that could be used on public roads.

John

Mr Whippy - 6/1/09 at 12:41 PM

quote:
Originally posted by mr henderson
quote:
Originally posted by cd.thomson
Have you considered a two wheel BEC John, even better weight saving. Cornering would be okay, could probably use a handlebar arrangement and weight distribution.


Too dangerous. I'm thinking about a vehicle that could be used on public roads.

John


only as dangerous as you are, all down to the rider and their common sense

smart51 - 6/1/09 at 12:44 PM

you might save 40kg which is 10% of a light weight BEC. You'll have a chain drive instead of a diff and half shafts. Perhaps you'll knock half a second off a 4s 0-60 time.

Triton - 6/1/09 at 01:03 PM

Think mine is going to be a tad light then, oh well at least it will leave odd black lines everywhere...

It's not bikes that are dangerous it's muppets in cars who don't bother to look

YQUSTA - 6/1/09 at 01:09 PM

You want this then as seen on 5th gear

T REX

YQUSTA

russbost - 6/1/09 at 01:21 PM

The Grinnall has the reputation of being very quick in a straight line but likely to generate brown underpants when cornering as it tends to snap to oversteer rather rapidly - I have no idea if the reputation is true as I've never driven one.

"only as dangerous as you are, all down to the rider and their common sense" - wouldn't entirely agree, although that is a large part of the story, unfortunately as has already been said it doesn't allow for the idiots that "don't see you"

Mr Whippy - 6/1/09 at 01:30 PM

quote:
Originally posted by russbost
"only as dangerous as you are, all down to the rider and their common sense" - wouldn't entirely agree, although that is a large part of the story, unfortunately as has already been said it doesn't allow for the idiots that "don't see you"


the common sense bit is also assuming they haven't see you, which is why I slow down while going past junctions and will stop if I don't think they have. Dressing in appropriate high visibility gear and riding with the lights on. It's quite amazing how many fail to manage even these basic things, but that’s bikers for you.

[Edited on 6/1/09 by Mr Whippy]

02GF74 - 6/1/09 at 01:34 PM

even driving defensively is no guarantte - I've had people give me eye contact then pull out in front - then say "oh, sorry, wasn't thinking!!"

There is nowt you can do about that.

jimgiblett - 6/1/09 at 02:09 PM

quote:
Originally posted by russbost
The Grinnall has the reputation of being very quick in a straight line but likely to generate brown underpants when cornering as it tends to snap to oversteer rather rapidly - I have no idea if the reputation is true as I've never driven one.


I have driven a Grinall (about 18 years ago) and found it to be a complete hoot. Mark Grinnall took me out for a spin and then let me have a go. The biggest problem was getting traction as the rear wheel is always in the crappiest part of the road. I only had the opportunity to drive it two up which I think will be significantly more stable than when driving solo as the inside front tries to lift on tight bends which if a left hander tries to tip you out of the car.

I would make a place for it in my garage should one come up cheap enough.

- Jim



[Edited on 6/1/09 by jimgiblett]

Mr Whippy - 6/1/09 at 02:16 PM

quote:
Originally posted by 02GF74
even driving defensively is no guarantte - I've had people give me eye contact then pull out in front - then say "oh, sorry, wasn't thinking!!"

There is nowt you can do about that.


true but its the cars wheels I'm looking at, you can see them rotating before anything else and if there are not perfectly still then I slow right down to where I can stop if they pull out. Honestly I just doddle around I have no need for speed. Like you say people looking at you means nothing, their not even looking really, just turning their head and staring into space.

jimgiblett - 6/1/09 at 02:22 PM

quote:
Originally posted by 02GF74I've had people give me eye contact then pull out in front


Me too 20 years ago. Woman inched forward out of her drive looked left and right (got eye contact) and then pulled out straight in front of me on my m/bike.

And if it wasnt for a lot of luck (nice soft hedge/ditch to land in) I probably wouldnt be here now.

I picked myself up out of the ditch limped down to my bike (now with no handle bar or fairing) dragged it to the side of the road. Then walked back to the woman.

Woman offered me an alcoholic drink to settle my nerves while we waited for plod to arrive(I refused)

- Jim

Mr Whippy - 6/1/09 at 02:53 PM

quote:
Originally posted by jimgiblett

Woman offered me an alcoholic drink to settle my nerves while we waited for plod to arrive (I refused)

- Jim


superb must remember that one

idl1975 - 6/1/09 at 04:59 PM

In my experience, and having extensive experience of both common configurations, the 2 wheeled version is far, far more forgiving than the 4 wheeled one. It even automatically countersteers for you if you use a bit too much throttle.

The only things they can't do as well are brake as hard into corners and carry a sofa set (I'm treating Goldwings and K LTs as small cars for this purpose).

So if the trike setup is really a bit snappy, the best way to go is just buy a bike.

[Edited on 6/1/09 by idl1975]

mr henderson - 6/1/09 at 05:57 PM

quote:
Originally posted by idl1975
In my experience, and having extensive experience of both common configurations, the 2 wheeled version is far, far more forgiving than the 4 wheeled one.


It's actually the 3 wheeled version that I was wondering about.

Guinness - 6/1/09 at 07:19 PM

I really seriously considered the Malone Skunk when deciding on a kit to build.

http://malonecar.com/Home.html

I also really like the concept of the Aprilia Magnet. (Admittedly I'd rather use a petrol engine and chain drive than the magnets / batteries).




Mike

Simon - 6/1/09 at 08:17 PM

Hubless wheels - cool

Seen Grinalls at Brighton ST's and quite quick, though I'd imagine bendy bits'd be interesting.

I modelled a single seat trike about 20 years ago that may yet see the light of day

ATB

Simon

[Edited on 6/1/09 by Simon]

russbost - 7/1/09 at 01:49 PM

To add some stability & rear grip for very little extra weight you could keep the trike format but add a second rear wheel, I can't remember the dimension but provided they are not too far apart it is still treated as a trike for all legal purposes.