Try again; any suggestions for a small lightweght pre-engagement type starter notor?
cheers
|Bob

I'd kinda think that a starter motor isn't going to do the job??
(correct me if I'm wrong, guys).

When people talk electric reverse they usually run on a cog either just in front of the diff or on the halfshaft.

From my extensive experience trying to start a car while it's in gear (A long time ago, honest), the starter motor didn't really make the car leap with power. And that would have been against a flywheel (large diameter, hence high ratio) first gear (again high ratio) then through the diff (again dropping it down).

I think a straight startermotor isn't going to cut it without some gearing being involved.

Am I wrong?

- Greg H

i think that the electric reverses are usually attached to the diff, with a suitable gear ratio involved to give it enough umph...!

never seen one though, maybe repost it in the BEC section? they must know.

Hi guys - I've got no worries about making it work, I just want a small neat one that won't weigh more than the rest of the car put together. I was hoping for replies like "get the one off a hondhai dingbat, it weighs 200grams and is attatched with stickytape". I've asked at the parts shop (for recon) but they ain't got a clue, they just get the number out of the catalog.
Cheers
Bob C

small lightweight pre-engagement type starter motor?

Hi I am not sure but I would have suggested using an solenoid engaging motor then you could either remove the soloide and lock the position you what, or use an electrical inter lock to prevent you engaging reverse unless the neutral indicator from the bike engine is on and you want reverse such a starter motor can be found on SARB 900’s although it is not the lightest of starter motors.

Failing that the motor that MK sell in there reveres kit looks like windscreen wiper motor have you investigated that avenue.

Or if both of the above suggestions seem like a bad idea and you don’t mind paying a bit try one of the Robot was shops on the web and have a look at there collection of 12V motors and gearing. This will cost a bit more but you should be able to get a much lighter/smaller/lower current draw motor for a reasonable price.


Hi again

Remembered that some windscreen wiper motors have a plastic worm gear that I is reasonably easy to shred so you would probably need one with a metal worm gear for a longer life it is easy to check the type of gear by simply removing the back plate at the drive end of the motor.


[Edited on 23/9/03 by ceebmoj]

Dunno about the pre engaged bit, but iv'e heard of peeps using CBR600 starters for electric reverse setups. The starter on my ZX9 is tiny, but as to it being powerful enough????

Al.


i]Originally posted by Bob C
Try again; any suggestions for a small lightweght pre-engagement type starter notor?
cheers
|Bob

Cheers - I'll check out the MK offering. Bike starters seem to be ratchet engaged rather than pre- engagement - the last thing you want on an electric reverse!
TTFN
Bob C

Whatever you choose, using something that's commonly available will make life much easier in the future, when it eventually breaks down

David

Remember... When you start a car in gear, not nly are you turning the wheels, but you are also cranking over a a big air compressor. At least until it fires up and becomes an engine.

The pre fab units are neat in the fact that they swing out of engagement when the car moves forward.

By the way this is my 1st ever post on this site. My Ron C. book just came in the mail today.

Some ford escorts and fiestas have a very small starter motor which might do the job.they are pre engaged but you could remove the solenoid and use a seperate one and modify the pinion etc if needed.
Paul.

quote:

---

Originally posted by Bob C
Hi guys - I've got no worries about making it work, I just want a small neat one that won't weigh more than the rest of the car put together. I was hoping for replies like "get the one off a hondhai dingbat, it weighs 200grams and is attatched with stickytape". I've asked at the parts shop (for recon) but they ain't got a clue, they just get the number out of the catalog.
Cheers
Bob C

---

I'd never realised that you had to have an electric reverse for bike engined cars... though i know bikes don't have reverse.

I'll ask my dad's boss tomorrow, he had a bike engine in his car.... see if he knows what they used !!!

radical use the powertech/quafie thing for reverse, is big an hefty and costs about 2 and half grand iirc, there is also another similar to that made by qaife only nothing to do with powertech, bit cheaper but still a bit pricy and is quite hefty.
ive designed my own and am still waiting for quaife to get back to me (been a good few months now since i sent the design) something tells me theyre waiting for a patent application to come back, but thats me being paranoid and they'd have a problem anyway cos ive already patented it. anyway, some blatent plugging here but if it is as it looks then it should be extemely light, probably comparable to the weight of the electric reverse, plus has no moving parts when in foreward (not even a bearing) so is 100% efficient, just has some gears turning when in reverse, so chain wax or grease/heavy oil should be enough lubrication which means it doesnt need a casing around it to keep oil inside either.
i got worried at one point, when talking to some radical owners, they said that having a chain in the drive system would reduce reliablity (obviously the chain is going to be under more strain than in a bike), but if you look at the quiafe/powertech unit, it actually has a chain inside it from where the engine plugs in to where the gearbox part is.
unfortunately as i said, im still waiting for quaife so ive no idea on actual weight or price, but here is a 3d image of what is it should look like-
Rescued attachment gearbox.jpg

ps- it just bolts onto a quaife atb diff like you would use with the mk electric, and tehn you just need a lever to move the selector fork (the big yellow thing).
the foreward mech is held engaged by springs so the fork doesnt have to do anything in foreward hence no wear.
and those 2 blocks with the teath on them bolt ot the chassis as part of the reverse mechanism.

[Edited on 29/9/03 by suparuss]
Rescued attachment gearbox2.jpg

You need to have a look on the Yahoo BEC site/forum they are all talking about taking reverse units off, so at the very least there could be some units going cheap.

I'll probably do ford fester - they're fairly neat & lots around. Cheers for the ideas lads. Suparuss - looks good but I'll have a prop (just found a 3.14:1 sierradiff for £50) The price of any 1-offs with cogs will have a lot of zeros at the end.... I'd have said it was only practical if you could do it at home (not impossible witha decent lathe + dividing thing). Plus it looks like you have a kind of swash plate actuation which would be a goggle to machine. Good luck anyway!
Cheers
Bob

cheers, i thought the mk electric reverse was for mid mounted bike engines?
there is no swash plate, the thing that looks like it is, is just connected straight inside the casings via 4 shafts and acts as the shafts for 4 componeatns inside that lock the box in foreward gear.
from the start quaife have been saying that they have been working on a similar design and today they told me it was radical, but they apparently have a "design copyright" which i think is superceded by a design patent if the invention already patented is part of that design?? getting complicated now,.
i never planned on buying just a one off, which would obviously be expensive, will hopefully be able to shift a few to mid engined car owners, or even radical!! hehe, just the legal stuff to get out the way.