Sonic7
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posted on 8/5/10 at 11:12 PM |
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Team MEV - tR1ke
At long last Team MEV launch a video of the tR1ke in action
http://www.youtube.com/watch?v=sfaNVup27Z0
This could be my next project, interested to know what do people think of it ?
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bmseven
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posted on 8/5/10 at 11:50 PM |
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NiIce
BMW 7 Resource
Bures Pit anyone?
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Peteff
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posted on 9/5/10 at 07:52 AM |
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It looks too long and low from the side, too much car and not enough bike like someone took two thirds of a car and stuck half of a bike on the back.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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02GF74
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posted on 9/5/10 at 08:57 AM |
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naughty - doesn't appear to be road registered.
can't say I like the look of it.
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whitestu
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posted on 9/5/10 at 08:57 AM |
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I really like that - very sensible approach to using a bike engine.
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zilspeed
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posted on 9/5/10 at 09:03 AM |
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quote: Originally posted by Peteff
It looks too long and low from the side, too much car and not enough bike like someone took two thirds of a car and stuck half of a bike on the back.
That's because that's what they did though
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The Venom Project
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posted on 9/5/10 at 09:31 AM |
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R1 Trike
Its a lot of money for not that much kit really.
£4000 plus vat and you dont get wheels
You have to source a decent R1
Because it qualifies for MSVA you don't need a reverse so they don't even offer one or even have one available. The seats look shite that
come with it, if you request you don't want the seats they don't offer a discount. I found just speaking to them weired as they seemed to
think this would crush the reverse trike market.
I reckon I will spend my money on either a T3 Secma, Grinnall Scorpian or Malone Skunk.
Far far better vehicles, all of which have reverse and all look worth the money you are spending.
If I was really flash I would buy a Campagna Trex but they are a touch much at $58,000
It's not that i'm lazy, it's that I just don't care.....
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tegwin
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posted on 9/5/10 at 09:55 AM |
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Sorry.. doesnt appeal to me..
Any any company who cant be bothered to use a tripod when filming promo material and then puts that crappy music over the top wont get my money!
------------------------------------------------------------------------------------------------------------------------
Would the last person who leaves the country please switch off the lights and close the door!
www.verticalhorizonsmedia.tv
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Dangle_kt
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posted on 9/5/10 at 10:41 AM |
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I like it - crap video though, they would be better using that little "race" track they have used on the other vids. At least they could
do more than 2 mph and be legal.
I dont think it is the best MEV product though - the sonic is my current favourite.
Good thing about kit cars is they dont need to appeal to everyone.
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scootz
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posted on 9/5/10 at 12:21 PM |
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Me no likey...
It's Evolution Baby!
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big_wasa
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posted on 9/5/10 at 02:58 PM |
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I like the front. Hmm I like the whole thing.
About 50 other cars I would spend that much on before it.
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smart51
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posted on 11/5/10 at 05:31 PM |
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How heavy is it? I'd want it to be a lot lighter than a seven to be worth losing the extra wheel. Looks like fun though.
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David Jenkins
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posted on 11/5/10 at 06:11 PM |
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I don't think it's that bad - I've seen many worse.
Bit daft to drive it on the road unregistered, AND post a video of it!
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Sonic7
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posted on 11/5/10 at 09:56 PM |
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Thanks for all the comments I suppose It's a little bit like Marmite (love it or hate it ?)
Found another video of it today, that's a little bit more exciting.
http://www.youtube.com/watch?v=WszJnYxvYz0
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beaver34
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posted on 11/5/10 at 10:14 PM |
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quote: Originally posted by smart51
How heavy is it? I'd want it to be a lot lighter than a seven to be worth losing the extra wheel. Looks like fun though.
345 kg says on YouTube
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smart51
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posted on 12/5/10 at 07:14 AM |
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quote: Originally posted by beaver34
345 kg says on YouTube
So potentially 20% faster than a seven with the same engine. Sounds good already. I bet snap oversteer is a bit of a problem when it loses traction.
That might be "fun".
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iank
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posted on 12/5/10 at 07:45 AM |
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The real problem with RWD reverse trikes (and I'm a fan) is you need to be very aware of their handling 'issue' if giving it the
beans out of a tight corner.
http://www.clevislauzon.qc.ca/Professeurs/Mecanique/ethierp/3-wheels/class3.htm
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
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vealmike
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posted on 3/6/10 at 12:20 PM |
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quote: Originally posted by iank
The real problem with RWD reverse trikes (and I'm a fan) is you need to be very aware of their handling 'issue' if giving it the
beans out of a tight corner.
http://www.clevislauzon.qc.ca/Professeurs/Mecanique/ethierp/3-wheels/class3.htm
The website you've linked to is almost correct.
The real problem with a 2F1R rear wheel drive trike is balancing traction with the centre of gravity.
The goal of a designer should be to ensure tha the tyres lose traction and slide before the trike starts to tip.
To determine when the trike will tip, we need to draw an imaginary line from the trikes centre of gravity to the ground. Imagine a string with a plumb
bob attached.
The line represents the sum total of all the forces acting on the CofG.
As the trike accelerates, then the point at which the line intersects the ground will move backwards. Braking will move the point forwards. Turning
right will move it to the left. You get the idea.
Keep this idea in your head, and now draw a triangle between the contact patches of the three tyres.
If the point at which our imaginary line intersects the ground falls within the contact patch triangle, then the trike is stable. However, if the
contact patch falls outside the triangle, then the trike falls over.
To increase the trikes resistance to tipping, the centre of gravity needs to be moved towards the centre of the two wheel axle.
The website fails to realise that widening the distance between the two front wheels also widens the contact patch triangle and therefore increases
the resistance to tipping.
With a motorcycle engine in a trike, it is debatable whether a front engine or rear engine layout is better. With a driver only, front engine is
probably better. With a passenger as well, the occupants will outweigh the engine, so a rear engined solution is better.
The worst possible soultion would be one where, say, for example, a single driver sits high, near the rear wheel over a battery and electic motor -
and the distance between front wheels is narrow.
OK, that describes how to control how much force is required to tip the trike and where to place CofG to maximise the cornering (or combined cornering
/ accerlerating / braking) forces required to make the trike tip.
This theory applies to ALL vehicles, not just trikes by the way.
I also said that traction is an important part in trike safety. It is, but here the designer has less to play with. It is simply a case of ensuring
that the trike is not over tyred. If the tyres fitted are too sticky, then it will be possible to generate enough force (usually cornering) to tip the
trike.
Front wheel drive trikes do have some immunity to acceleration + cornering induced tipping, so it's worth noting that they are a special case.
It's really simple - turn hard and accelerate and the inside wheel will lift. As soon as it does, the diff will spin the lifted wheel, and power
to the wheel on the ground will be lost. As acceleration is lost, the forces acting on the CoG move forwards again and the trike regains stability.
I hope that lot helps explain the detail.
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iank
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posted on 4/6/10 at 08:07 AM |
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Actually if you read the whole website (he seems to be a prof of mechanical engineering btw to I'd expect his maths to be sound) it's safe
to say he completely understands that widening the front track helps given this diagram elsewhere on the site, which diagrams the cog triangle/pyramid
you describe.
IMO any car has to be safe with both single driver and driver+passenger and while it's a characteristic that can be controlled/avoided if you
are expecting it it does seem to be very common with RWD BEC (BET?) designs (both Grinall Scorpion and T-rex are pictured lifting their wheels) since
the wheels really have to be VERY widely spaced to overcome it in all circumstances.
You're right that the diff automatically saves you on a FWD design as well as the weight distribution advantages. Memo to self be cautious of
LSD's in FWD trikes
--
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 4/6/10 at 10:01 AM |
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How about grafting a bike onto the rear-end of a space-frame single seater (ex-Formula Ford???).
It's Evolution Baby!
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vealmike
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posted on 7/6/10 at 11:20 AM |
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quote: Originally posted by iank
Actually if you read the whole website (he seems to be a prof of mechanical engineering btw to I'd expect his maths to be sound) it's safe
to say he completely understands that widening the front track helps given this diagram elsewhere on the site, which diagrams the cog triangle/pyramid
you describe.
Yup, you have me there, I did not read the entire website, just the one page. It wasn't obvious from that one page that the guy fully grasped
what was going on.
Still, in my defence, understanding what is going on with CofG in a trike is so very important to driving one safely that re-posting this info is
probably a good idea.
Every Trike pilot should know this stuff inside out IMHO.
quote: Originally posted by iank
IMO any car has to be safe with both single driver and driver+passenger and while it's a characteristic that can be controlled/avoided if you
are expecting it it does seem to be very common with RWD BEC (BET?) designs (both Grinall Scorpion and T-rex are pictured lifting their wheels) since
the wheels really have to be VERY widely spaced to overcome it in all circumstances.
I don't think you can overcome it in all situations. Which is why it's vitally important to understand what's going on.
For example, a single driver in a right hand drive trike (2 seats side by side) will always corner faster to the right than to the left. Worth knowing
that when a passenger is added, cornering speed to the right decreases and to the left increases.
One that caught me out was camber on the road. I was making a 180 around a roundabout on a hill - effectively a banked turn. The banking flattened
whilst I was still turning, resulting in an airbourne inside wheel and a particularly blue string of expletives from my father in law in the passenger
seat.
Actually, I was very surprised at how controlable my trike was in bike mode.
I was gently accelerating at the time, I kept the power on and the wheel slowly lifted. Come off the power and it hovered nicely, a quick dab of the
brake was required to regain contact with terra firma. That said, I have not repeated the excercise.
quote: Originally posted by iank
You're right that the diff automatically saves you on a FWD design as well as the weight distribution advantages. Memo to self be cautious of
LSD's in FWD trikes
Yes, obviously fitting an LSD would allow you to keep the power on when a wheel comes up.
Once everyone understands the principals of trike stability, the next thing to consider is what would need to happen to "trip" a trike and
of course what the results would be. I don't wish to scare people, but I honestly believe that you should be aware of what the vunerabilities of
a trike are before you drive one.
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tony-devon
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posted on 10/6/10 at 09:41 AM |
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quote: Originally posted by scootz
How about grafting a bike onto the rear-end of a space-frame single seater (ex-Formula Ford???).
that sounds similar to what Im building
mike engined, bike front end, but the rear end is loosely designed around the haynes roadster, hence why Im on this site
IRS rear end, 110bhp shaft drive bike engine, should be in the region of 400kg finished, my motor once proven that it works well, will be force fed
eventually.
heavy is good, heavy is reliable, and if it breaks, hit them with it
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