Shifter solenoid choice?

[bringo]

A question for the teams that have made their own electric solenoid shifter systems. I'm looking into doing this for next year's car, and I'm having trouble finding a suitable push/pull solenoid. As others have said, the CBR600 gearbox requires about 25 lb of force to get the shifter moving with the stock 1" lever. The one company that had a promising solenoid listed on their website told me that it would burn up if it was cycled more than 5 or 6 times a minute. What solenoids have you had good experience with?

[IsheeM]

I would also like some information on this. I have been searching for quite a while now with no luck.

[Agent4573]

you could always try our route, a bit different but it seems to work for us. take an rc car motor and mount it to a 18 volt cordless drill transmission. Works like a charm, but you have to replace the brushes every year.

[Igor]

Try to stay away from the big coil and armature solenoids, they are ridiculously heavy for the little force they give. If you set it up just right it works most of the time, but not all the time. It usually lacks power to push through when the shift is missed.

After market trunk type solenoids aren't really solenoids, but a small motor with a plastic ball screw. This will get you far more power per weight, but they are designed to operate only occasionally and thus have thermal issues. I have a molten one lying around somewhere, but that one was really tortured. I also think they're not sturdy enough for this application.

I've seen a sweet version made by Lulea, which was an RC motor linked to a metal ballscrew with a pulse encoder for the control electronics. Lighning fast.

I like the cordless drill idea. Will it damage the transmission if it doesn't engage right away or isn't there enough force?

Igor

[Cement Legs]

Bringo, where did you get the 25 lb number? A couple of guys on our team welded a piece of hex-stock onto the splines so they could fit a socket over it. With a torque wrench they measured 45 lbs/in.

[syoung]

We use a unit by Kliktronik. They are a UK company but list US, Aussie and other distributors. It's fairly heavy, and subject to going wrong if you don't install it nice and straight, but it should do the job for us. Long-term (i.e. next year) I'd like to see us move on to looking at electro-pneumatic actuation.

[bringo]

The RC motor and drill transmission sounds like a good idea. I might have to give that a try. Unfortunately premade units like the Kliktronik are too expensive for our team.

Cement Legs - I just used a cheap pull-spring force gauge. 25lb is what it took to get the shifter moving. I didnt complete a shift b/c the gauge wouldnt read any higher, so your measurement is probably much better. Thanks for the info.

[Patrick W. Crane]

We use a solid linkage from the shifter to the engine made of carboin tubing and some bonded aluminum ends. Never misses a shift, nice light action, and weighs around 250grams.

But we have no elec guys on the team trying to convince us to do something silly

[Chris Boyden]

Another thing to look at is high speed linear dc motor drives.

[gug]

Originally posted by Igor:
I like the cordless drill idea. Will it damage the transmission if it doesn't engage right away or isn't there enough force?

Igor

im sure there are others around here that know more about transmissions than me, but AFAIK the only way to damage a motercylcle transmission is by shifting too slow. the dogs grind instead of engaging, and pretty quickly the transmission dies.

of course, thats in a normal application. we would probably stuff some other part of the engine before crappy shifting could destroy a gearbox.