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Why bike engines??
Gakes - 31/3/08 at 07:49 PM

Hi every1

I am in the process of building a middy but car engines I'm looking at are too big or too heavy or have too little power. I need to know why Bike engine builds are chosen. Are the vehicles quicker, better sounding,more exciting or whatever??? Please give some of the good and bad points. Thanks


grub - 31/3/08 at 07:59 PM

yes yes yes there are no bad points?


BenB - 31/3/08 at 07:59 PM

Pros

Powerful, light, cheap, rev quickly (low mass, light flywheel), rev like crazy, more exciting

Cons

No reverse, people with CECs get jealous and slag them off, high rpm cruising can get on your nerves after a while!! You have to keep the engine on it's toes (you can't just stick it in 5th and drive like on a V8)...


Hellfire - 31/3/08 at 08:00 PM

You've already found out for yourself Car engines are too big or too heavy or have too little power. Rand for rand, bike engines have better power, are very light, easy to install and sound superb.

There are no bad points. Okay, so it doesn't have reverse but thats not bad..... it's good.

Phil

[Edited on 31-3-08 by Hellfire]


LBMEFM - 31/3/08 at 08:01 PM

Don't really know that much about it, but I am building a bike engined car. The reason I chose it is that the engine is very light and complete with gearbox, has a six speed sequentual gear box and has an excellent power to weight ration. The only downside I can see is that it lacks torque at low revs and constant gear changes are required. By the way sounds good too.
Barry


Gakes - 31/3/08 at 08:07 PM

thanks guys, looks likle the bike engines win the battle ALMOST!

No reverse gear is a bit off-putting. I want to use the car on the road as well


Jon Ison - 31/3/08 at 08:08 PM

quote:
Originally posted by Dragon-Performance-Eu
quote:
Originally posted by BenB
(you can't just stick it in 5th and drive like on a V8)...


erm sorry but I have to disagree, my bike engined car could be left in 6th and still have enough grunt/torque for safe rapid overtakes, as any of my passengers can attest to.....



I have to 2nd that.


worX - 31/3/08 at 08:11 PM

Thirded!
Maybe not exciting overtakes, but lazy roll-ons are simple...

Steve

ETA - Mine is a road car and I haven't a reverse and no desire to have one fitted - I wouldn't do it if it were free! Since when was it fun (in reality!) to drive backwards?

[Edited on 31/3/08 by worX]


Hellfire - 31/3/08 at 08:11 PM

quote:
Originally posted by Gakes
thanks guys, looks likle the bike engines win the battle ALMOST!

No reverse gear is a bit off-putting. I want to use the car on the road as well


Ours is used on the road too, as well as track and the lack of reverse has never been a problem for the last four years.

Phil


quinnj3 - 31/3/08 at 08:12 PM

i might be stealing this topic but its along the same lines and i'm sure you'll be interested anyway. A couple of years ago i bought a kit car mag (forget which one) and featured was a quantum??? with a v8 bike engine. Basically it had a custom block with 2 R1 heads, rev'ed to about 10k and had around or over 300 BHP. Now that would knock down the lack of torque argument. I think the engine alone cost 10k


itiejim - 31/3/08 at 08:14 PM

I've got an electric reverse on mine, cheap simple and (so far!) reliable. Plus of course you get the washing machine comedy factor

My Blackbird engine has certainly got plenty of steam, no problem with lack of torque either.


Gakes - 31/3/08 at 08:24 PM

Electric reverse!?!?!?!

That sounds awesome!Please do explain how you did that because if thats possible and cheap enough in South Africa Im totally bets for this


BenB - 31/3/08 at 08:24 PM

I wasn't saying BECs don't have torque (I've got a ST1100 after all with 71.8@5500rpm) I'm just saying it's a bit different to a big dollop of V8 or V12 grunt. Then again, I like stirring the stick a bit whilst driving (especially on a sequential box)...


Humbug - 31/3/08 at 08:25 PM

At the risk of getting flak from the BEC boys, what about the *apparent* fragility of bike engines? There seem to be more stories of bike engines blowing up, dropping a bollock, or whatever than car engines.

(lights blue touchpaper and retires to a safe distance)


JoelP - 31/3/08 at 08:28 PM

they are not as unreliable as you might think. Ive had 5 failures at track days, this was a fuel pump, a rad hose, a gear link, a coilover, and one more i forget. Never broken the actual engine, and not for lack of trying.


Gakes - 31/3/08 at 08:29 PM

Please inform me of the electric reverse guys.

And Humbug, before you end up in the gutters somewhere, You have raised a good point.


Wheels244 - 31/3/08 at 08:30 PM

Fit a reverse box - I have.

Personally I don't want to look a pillock having to get out of it to push it backwards for parking etc......


Gakes - 31/3/08 at 08:36 PM

C'mon ppl, how reliable are these engines in cars?


Ivan - 31/3/08 at 08:40 PM

quote:
Originally posted by Hellfire
Y Rand for rand, bike engines have better power,
Phil

[Edited on 31-3-08 by Hellfire]


Your roots are showing Phil


Hellfire - 31/3/08 at 08:43 PM

ZX12R, fitted 2005, covered 8,000 miles on road, track and drag strip. Thrashed to within an inch of it's life most of the time. Just regular oil and filter changes and no mechanical problems whatsoever.

Bike engines, fragile?.............. NONSENSE.

Phil


Hellfire - 31/3/08 at 08:44 PM

quote:
Originally posted by Ivan
quote:
Originally posted by Hellfire
Rand for rand, bike engines have better power,
Phil

[Edited on 31-3-08 by Hellfire]


Your roots are showing Phil



grub - 31/3/08 at 08:58 PM

where are you going to want a reverse ,just park a bit futher up road lad or a quick stab on the loud pedal and ya facing the other way or still the same way if you make it fart loud enough


BenB - 31/3/08 at 09:01 PM

quote:
Originally posted by Wheels244
Fit a reverse box - I have.

Personally I don't want to look a pillock having to get out of it to push it backwards for parking etc......


But then I don't want to look a pillock sat by the side of the road when my reverse box springs a terminal oil leak, glows red hot and stops working, thereby killing the entire drivetrain

I would fit an electric reverse if I had the chance now though!!!


coozer - 31/3/08 at 09:03 PM

quote:
Originally posted by Humbug
At the risk of getting flak from the BEC boys, what about the *apparent* fragility of bike engines? There seem to be more stories of bike engines blowing up, dropping a bollock, or whatever than car engines.

(lights blue touchpaper and retires to a safe distance)


I'm with you there Humbug. I used to have a ZX9R Striker and when it came to choosing my new one I searched on here for which engine was the best for a BEC and was amazed to see how many bike engines have given up the ghost! Gear dogs, thrown rods, engines going BANG! etc.

Although I choose a car engine this time I decided after looking at the price of installing and updating it later to a turbo with 300bhp. Much cheaper than a decent bike (ZX12 or Busa) engine.

Its horses for courses of course, if you want a BEC go for it!!


Dale - 31/3/08 at 09:29 PM

I cant say from experience at all but I would think it would also depend on if you are a big guy - over 200 lbs or more and if you want it to perform the same with a passenger. I always thought hp per tonne should be given with the drivers weight included.
Dale


Wheels244 - 31/3/08 at 09:40 PM

Ben is that from personal experience ?

Lot of people use the Quaife box - can't be all bad.
Mines under warranty - if it dies I'll get a new one


Humbug - 31/3/08 at 09:50 PM

as far as I remember, homemade leccy reverse is usually done with a starter motor engaging with a sprocket on the propshaft, with your choice of switching, etc. to try to make sure you don't engage it while in a forward gear, or over-running it, etc.


CaptainJack - 31/3/08 at 10:03 PM

bike engines are more highly tuned that car engines and rev harder so need to look after them, but regular oil and filter changes with good quality parts will look after them. Also i guess that the fact the engine only ment to haul maybe 250-300kg about in its normaly fitment it wont like the fact its needs to cart swo much extra weight about, maybe thats why some give up


Jon Ison - 1/4/08 at 06:17 AM

Can someone please list this long list of fragile bike engines that have gone bang ?

Tuned blade, over 15k miles in car, thrashed to **** everywhere.

Off the top of my head here is a short list of CEC engines that have let me down during my "racing" days.

Blown, Pinto x2, mini (bmc) blown countless, 205 block atmo cosworth (blown) RV8 blown. Peugeot 205 blown x 2. Blade, cant blow the dam thing, still waiting to upgrade to a ZX12R, guess it will let go one day.


MikeCapon - 1/4/08 at 06:27 AM

Hi, here are some piccys of electric reverse setups.

As for reliability, a well looked after bike motor can be regularly thrashed to within an inch of it's life. What they don't like is abuse, ie massive over rev on down changes or clumsy, violent gearchanges.

rev1
rev1


rev2
rev2


MikeCapon - 1/4/08 at 06:30 AM

Another:-


rev3
rev3


[img]http://www.locostbuilders.co.uk/upload/electric_reverse[1].jpg[/img]


Gakes - 1/4/08 at 06:37 AM

Thanks for all the info guys. As far as the reliability goes, im not too sure yet. Still need to buzz around for a while.


Gakes - 1/4/08 at 06:42 AM

Are there any bike engined middys around. I would like to hear what they have to say.

BE's will bring the weight of my car down to a minimum! thats cool, but it shouldnt take up too much time maintaining it


BenB - 1/4/08 at 06:46 AM

quote:
Originally posted by Wheels244
Ben is that from personal experience ?

Lot of people use the Quaife box - can't be all bad.
Mines under warranty - if it dies I'll get a new one


I think the new Quaife one is probably the first one that does'nt have a reputation for dying. Still eats a %age of the BHP (okay it's small % )


Humbug - 1/4/08 at 07:13 AM

Not sure I like the idea of a circular saw blade whizzing round next to my thigh... even less that a honking great pole whissing round next to me


Hugh_ - 1/4/08 at 07:19 AM

quote:
Originally posted by Gakes
Are there any bike engined middys around. I would like to hear what they have to say.



Looking at Mike's last photo where you can see the engine about 300mm forward of the diff I'd guess that's middy. Quite happy to be corrected though.


MikeCapon - 1/4/08 at 07:38 AM

Yes, tis a middy. Built in the states with a Kawasaki motor. Odd hot rod looking car with the bike front end! I'm trying to find the link now


Jon Ison - 1/4/08 at 08:15 AM

Bike engines are even more reliable in a middy, the engine is mounted more like it was in the bike.

Ran a blackbird motor know as the "cat" it used a fair few of its lifes up.

Blown oil cooler hose followed by a fire, survived.

lost sump plug, survived.


MR2 - 2/4/08 at 03:21 PM

reliability is the person driving and maintaining it. EPR, anyone thought about using a multy V belt with a magnetic coupling used on airco pumps? In combination with an reduction starter with a pully. Big circlesawblade doesnt get me going either. You can always make a flintstone trapdoor for FPR


phil T5 - 15/6/08 at 04:36 PM

Not an expert, a new kit car owner but from my limited experience chose a cec.

I had passenger ride in fireblade bec and sounds beautiful, bit harsh gear changes etc but a real different experience to a normal car. But isnt that why we get these cars any way.

However as a lot of my driving is with a passenger I needed more torque and ultimately power, so went for a cec with 235hp xe engine.

Its heavier than a bec, around 600kgs, but has reverse, revs to 8500rpm, sounds mean, high 5th gear, 3000 rpm at 75mph and its quick enough around 400hp/tonne.

Must admit though I still love the idea of a bec, in some ways its a purer concept, light weight and loads of revs and may one day go for this one i've been let in gently to this new experience by cec

Both are great!


richardh - 16/6/08 at 08:31 AM

i have a quaif reverse on my BEC and its great. Got to reverse slowly though but enough to not have to get out and push. cost about 600-700 for it and it adds to the weight but i found it better thatn an electric one.

all depends on how oftern you are going to be driving in towns and might need that reverse.....................