Siduna
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| posted on 14/3/12 at 07:32 AM |
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Mid engined BEC
Hi!
I'm collecting parts for a mid engined BEC build. Need some input/advise to move forward.
I'm not too keen on an electric reverse and adding a reverse gearbox between the engine (turboed Hayabusa) and a rwd car diff puts the engine
way to far forward. I'm nursing the idea of using an Audi transmission (A4?). The idea is to use a clutch center and make an adaptor for a
"cardan joint" (wrong word?) and connect it to the outgoing shaft on the engine also using an adaptor (available "on the
market" and a short prop shaft in between I'll use a support bearing for the "clutch center adaptor" mounted to the gearbox
casing (using the interface for mounting onto the car engine.
Has this been done before?
Ideas and thoughts?
Writing with a broken pencil is pointless
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Andy B
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| posted on 14/3/12 at 07:48 AM |
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Seems massively complex and inefficient, not mention heavy way of doing things. Why not just turn the engine round, chain drive a powertec reversing
differential.this will be cheaper, lighter, hugely more efficient and maintain the engine in it's usual orientation. It's tried tested and
we use it in the Sabre race cars we build and it's just about bomb proof
Regards
Andy
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edsco
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| posted on 14/3/12 at 08:21 AM |
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Either what Andy B said, like he said tried and tested, or perhaps use an Elite diff with built in reverse. More expensive option mind you....
edsco
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Stott
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| posted on 14/3/12 at 08:52 AM |
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I've got a quaife powertec qba7r in mine and it's the business fair play, not cheap though.
Andy, if your reading this, sometimes my diff though will lock between forward and reverse, the selector is all the way over until it's touching
the Ali mount but the diff will only go forward or backward 3/4 of a turn then it locks. Have you had any with this problem?
When I pop it in forward then, it works and won't lock for maybe a month or more?!?!
It's still the business though 
Edit sorry for the thread hijack 
[Edited on 14/3/12 by Stott]
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BobM
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| posted on 14/3/12 at 10:01 AM |
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quote:
Originally posted by Siduna
I'm not too keen on an electric reverse
Why? On a mid-engine install it's pretty easy and works well. Cheap, pretty light, what's not to like?
Adding a car transmission will as Andy says add loads of weight not to mention the additional frictional losses.
Not very Locost but very BEC 
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designer
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| posted on 14/3/12 at 11:14 AM |
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quote:
I'm not too keen on an electric reverse
Agree, there is nothing wrong with it! How much time do you spend in reverse?
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Siduna
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| posted on 14/3/12 at 11:47 AM |
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I started out with the intention of using chain drive (a Celica torsen diff to sort the cornering issues).
Then I got all these comments that a chain wouldn't take the load enough to be reliable. I'm looking at approx 300hp and roughly 600kg.
Thank's for the advise ... but I have to admit I feel a bit like a donkey between two haystacks.
What life expectancy can I expect with the power and weight according the above?
Writing with a broken pencil is pointless
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russbost
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| posted on 14/3/12 at 12:27 PM |
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We use a chain drive with electric reverse using the standard Toyota MR2 Mk1 starter on the Furore F1. Works a treat as long as you don't want
to reverse up a 1 in 7 or something like that & both cheaper & lighter than the gearbox alternatives. The chain should take it no problem,
they run drag bikes on the same size chain you can use IIRC it's 530 or 626. We're running the ZZR1400 engine with wide rear tyres &
mid engine, ok it's a bit less powerful & a bit lighter than what you're suggesting, but the first thing to break will always be the
adhesion of the tyres to the road even on a hot day on slicks. All IMHO of course!
I no longer run Furore Products or Furore Cars Ltd, but would still highly recommend them for Acewell dashes, projector headlights, dominator
headlights, indicators, mirrors etc, best prices in the UK! Take a look at http://www.furoreproducts.co.uk/ or find more parts on Ebay, user names
furoreltd & furoreproducts, discounts available for LCB users.
Don't forget Stainless Steel Braided brake hoses, made to your exact requirements in any of around 16 colours.
http://shop.ebay.co.uk/furoreproducts/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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coyoteboy
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| posted on 14/3/12 at 12:35 PM |
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Using a bike engine to drive a car box is quite frankly a bonkers way around electric reverse (unless I've read it wrong?). It's akin to
choosing to enter an F1 race with a mondeo because you don't like wearing helmets.
Elec reverse is tried and tested and pretty easy to set up. Will weigh what - 20kg at most?
[Edited on 14/3/12 by coyoteboy]
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eddie99
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| posted on 14/3/12 at 01:19 PM |
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Yup as above, i think its defeating the object of bike engine if you then want to use a car box. Use an electric starter on a sprocket on the rear
axle. Very cheap and reliable solution.
http://www.elitemotorsporteng.co.uk/
Twitter: @Elitemotoreng
Facebook: http://www.facebook.com/pages/Elite-Motorsport-Engineering/153409081394323
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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Siduna
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| posted on 14/3/12 at 01:58 PM |
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Thanks for your input guys!
The reason for not using a chain drive is because the risk of short life time on a chain drive. As for "dragbike chains", they are non
O-ring type (referring to EK chains for dragrace applications) and according to their technical people that limits their life time. That's my
experience after >20 Rosing motorcycles as well.
According to the general agent for EK chains breakages are an issue in Radical racing.
A bit surprised to learn from you guys that chain drive is bomb proof. I'm not questioning you! Kinda strange to get such opposite advise
though.
What life expectancy do you have for a chain drive in aggresive driving?
Writing with a broken pencil is pointless
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russbost
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| posted on 14/3/12 at 02:22 PM |
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I've never owned any of my demonstrators long enough to see any significant wear!!
1,000 miles of aggressive use chain needed retensioning a couple of times (after initial stretch/bed in when adjustment is significant), but
couldn't discern any wear on either chain or sprockets - being realistic how many miles a year are you likely to do, many kitcars don't do
more than 1500 a year,some of which will be gentle use, motorway/dual carriageway etc. so even 3,000 mile useage (which I think would be very extreme)
would give a couple of years life probably.
TBH, if this is for road use, unless you have a death wish,or are fed upwith owning a driving licence then you're rarely going to see full
throttle. With 190bhp & 560kg, I find you have to seriously rein yourself in b4 some insanely silly speeds come up! Was out in the lanes with it
last w/e & I spent more time on trailing throttle than on the power!
I no longer run Furore Products or Furore Cars Ltd, but would still highly recommend them for Acewell dashes, projector headlights, dominator
headlights, indicators, mirrors etc, best prices in the UK! Take a look at http://www.furoreproducts.co.uk/ or find more parts on Ebay, user names
furoreltd & furoreproducts, discounts available for LCB users.
Don't forget Stainless Steel Braided brake hoses, made to your exact requirements in any of around 16 colours.
http://shop.ebay.co.uk/furoreproducts/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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Siduna
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| posted on 14/3/12 at 02:26 PM |
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quote:
Originally posted by russbost
I've never owned any of my demonstrators long enough to see any significant wear!!
1,000 miles of aggressive use chain needed retensioning a couple of times (after initial stretch/bed in when adjustment is significant), but
couldn't discern any wear on either chain or sprockets - being realistic how many miles a year are you likely to do, many kitcars don't do
more than 1500 a year,some of which will be gentle use, motorway/dual carriageway etc. so even 3,000 mile useage (which I think would be very extreme)
would give a couple of years life probably.
TBH, if this is for road use, unless you have a death wish,or are fed upwith owning a driving licence then you're rarely going to see full
throttle. With 190bhp & 560kg, I find you have to seriously rein yourself in b4 some insanely silly speeds come up! Was out in the lanes with it
last w/e & I spent more time on trailing throttle than on the power!
What dimension and make of chain do you use?
Writing with a broken pencil is pointless
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Siduna
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| posted on 14/3/12 at 02:30 PM |
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quote:
Originally posted by russbost
I've never owned any of my demonstrators long enough to see any significant wear!!
1,000 miles of aggressive use chain needed retensioning a couple of times (after initial stretch/bed in when adjustment is significant), but
couldn't discern any wear on either chain or sprockets - being realistic how many miles a year are you likely to do, many kitcars don't do
more than 1500 a year,some of which will be gentle use, motorway/dual carriageway etc. so even 3,000 mile useage (which I think would be very extreme)
would give a couple of years life probably.
TBH, if this is for road use, unless you have a death wish,or are fed upwith owning a driving licence then you're rarely going to see full
throttle. With 190bhp & 560kg, I find you have to seriously rein yourself in b4 some insanely silly speeds come up! Was out in the lanes with it
last w/e & I spent more time on trailing throttle than on the power!
What dimension and make of chain do you use?
Writing with a broken pencil is pointless
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Siduna
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| posted on 14/3/12 at 02:36 PM |
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I typically spend about 3000 miles on the bike a year so reaching 2000 in the car isn't totally impossible. Big country, few people and nice
roads where I'm at.
So you guys think I should revitalise the plans for using the torsen diff and a chain drive?
Oh, if the guy responsible for the spell check in iPhones steps out in front of you ... don' waste your brake pads...
Writing with a broken pencil is pointless
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russbost
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| posted on 14/3/12 at 02:50 PM |
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I'm using the standard size chain for the ZZR1400 which IIRC is 530, there is one slightly beefier than this which I think may be
626?(It's definitely 6xx), but there's not a lot of difference & it'snot so readily available. I just use an "O"
ring chain from Triple S, mainly because I can get it from a wholesaler, I'm led to believe DID "X" ring is about the best.
I no longer run Furore Products or Furore Cars Ltd, but would still highly recommend them for Acewell dashes, projector headlights, dominator
headlights, indicators, mirrors etc, best prices in the UK! Take a look at http://www.furoreproducts.co.uk/ or find more parts on Ebay, user names
furoreltd & furoreproducts, discounts available for LCB users.
Don't forget Stainless Steel Braided brake hoses, made to your exact requirements in any of around 16 colours.
http://shop.ebay.co.uk/furoreproducts/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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BobM
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| posted on 14/3/12 at 02:53 PM |
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Most of us in the RGB race series use DID ZVM2 or ZVMX 530 chains. As Russ said, after initial use these require minimal adjustment and I'm not
aware that we've had any breakages in RGB (we're running standard engines up to about 180bhp and Yoko 48R tyres). I'm aware some of
the bikesports guys have had breakages but don't know what chains they use, they are however often running tuned big bore Busas and slicks.
If this is a road car and the chain and sprocket alignment is perfect I don't see a big issue. Again agreeing with Russ use of sustained full
throttle on the road in one of these cars is generally inconsistent with either a long life or a valid driving licence!
Not very Locost but very BEC
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coyoteboy
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| posted on 14/3/12 at 03:09 PM |
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Chain life, in my limited experience with them, depends rather heavily on the accuracy of the parts that it's fitted to. If your diff hanging
and tensioning is wrong, even slightly, it'll die in a matter of miles. If you have a way of keeping that lot nicely aligned and tensioned
correctly it should be fairly bomb proof.
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eddie99
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| posted on 14/3/12 at 03:48 PM |
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In Bikesports i've only ever seen a radical break a chain, and that the guy said that the chain had been on the car 8 odd years so if your
worried about it, replace it but remember these radicals are running 200+ bhp and running slicks and they go when they are redlining on the start line
dumping the clutch. Something that doesnt regularly happen on the road or even trackdays.
http://www.elitemotorsporteng.co.uk/
Twitter: @Elitemotoreng
Facebook: http://www.facebook.com/pages/Elite-Motorsport-Engineering/153409081394323
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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Siduna
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| posted on 15/3/12 at 05:42 AM |
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What typical ratio between sprockets are you using and what tire diameter? Given the fact that I'm building a heavier car but with a more
powerful engine I guess the same ratio, after compensating for difference i tire diameter, could be a good starting point. I'll be running
245/15x45.
Writing with a broken pencil is pointless
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Siduna
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| posted on 18/3/12 at 01:30 PM |
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Sprockets
Ordered 16-front 48-rear sprockets today. 225/45x15 tires at the rear.
Feedback?
Starter driven reverse: -What not to do?
Writing with a broken pencil is pointless
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Siduna
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| posted on 7/8/12 at 11:04 AM |
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A brief update
Decided to go with twin 530 chains and electric reverse ... parts in manufacturing.
I'll be using drive shafts, spindles and hubs from a Mazda Miata. Aiming at 0,02-0,03 degrees camber gain per mm travel in the fron suspension
and a RC height at approx 30mm. Any comments?
Writing with a broken pencil is pointless
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Toprivetguns
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| posted on 7/8/12 at 11:46 AM |
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The whole point of a BEC, CEC or any performance kitcar is weight.
Keep it minimal and locost, if a chain fails it will be relatively cheap and easy to change.
Not sure how much an A4 transmission weighs. Over my 3 years of building ive used the phrase KISS.
Keep It Simple Simon
Only drive as fast as your angel can fly... !
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Siduna
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| posted on 7/8/12 at 02:14 PM |
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Transmission
As you can see above the idea with a A4 transmission is scrapped. The twin chains will add weight, I agree. But so does a complete diff house when
using a prop "solution"...
Should it turn out the twin chains increases the weight beyound driveability it can always scrap one a go single chain drive.
A lot of excercise and proper food in enough portions also reduces weight
Writing with a broken pencil is pointless
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Chet
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| posted on 9/8/12 at 05:24 PM |
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Why do you feel the need for twin chains?
As mentioned by others already, a properly aligned high quality chain is a proven solution.
I'm wondering if the dual chains may actually provide less service life due to the different wear rates and alignment issues.
Please keep us posted on your results.
Thanks
Chet
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