IanT Posted June 1, 2004 Share Posted June 1, 2004 Hi all, Anyone who reads the Yahoo BEC group will know the hassles I'm having getting a gear indicator to work on my Blackbird. Problem seems to be getting the standard motorbike speed sensor to work (it's redundant on the Caterham installation, superceded by the Stack wheel sensor) so I've had to power it up using only the Haynes wiring diagram as a guide. I'm consistently failing to get the voltage reading from TWO separate sensors (I refuse to believe they're both faulty and I refuse to buy a new one at £112.00). I've tried tapping into the Stack wheel sensor, which seems to work ok, but as the sensor is on the front wheel it means "training" the gear indicator on the road, which, as I've found out, is hit and miss to say the least. Could anyone who's wired in a gear indicator to their Blade/'Bird/other tell me exactly how you solved the problem of getting a reliable speed input? If you used the standard bike speed sensor (as plugged into the top of the gearbox) did you have to do anything clever to make the sensor work in the absence of the standard bike speedo instrument? TIA Ian. Link to comment Share on other sites More sharing options...
Mike Molloy Posted June 1, 2004 Share Posted June 1, 2004 Previous owner told me he had a gear indicator fitted, so it CAN be done. I found evidence of crimp terminals on the original bike sensor, but the wiring for the Stack sensor had also been broken in to, so not sure where he was getting the signal from. I guess you have studied the Haynes manual, but here's my take just to confirm: Sensor wiring 1) Black = Fused Ign power 2) Green = ground 3) Pink = speed signal out The section on sensor replacement says you should get a 0 - 5V signal (between green and pink) if the output sprocket is rotated. My questions: Have you tried hooking a scope up to it to see what the signal looks like? Or even the voltmeter as suggested in Haynes? If you're getting nothing (as in zero volts and no fluctuation) I'd be tempted to try a pull-up resistor to +12V (the black wire). Something like 10K ought to be pretty safe. If I have time tomorrow I'll chop the heat shrink off my sensor wires and see what I get. What make of digital gear indicator have you chosen? Why do you feel the need? Keep reaching for 7th? I guess the short overall gearing makes the box *very* close ratio... Cheers, Mike. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Mike, Thanks for that. Yes, I've tried the same procedure as in the Haynes manual for testing the speed sensor. I would get a small voltage variation (0.16V) when the sensor was connected to the gear indicator but none when it's isolated. I've actually had a response from Acumen (I bought a DG8 gear indicator) who say that the speed sensor won't work without a shunt resistor from pink (speed sensor output) to ground, which is already built into the bike speedometer. Oops. This explains why I would get a very small signal from the sensor when it was connected to the DG8 but absolutely nothing when testing the sensor on its own. Ian. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Oh, nearly forgot ... yes, keep reaching for 7th, especially on the track Ian. Link to comment Share on other sites More sharing options...
charlie_pank Posted June 2, 2004 Share Posted June 2, 2004 Surely t's much easier to just learn to remember which gear you're in than fit a sensor - especially given the trouble you're having! A squillion bikers manage, and presumably you would only reach for 7th when you reached the rev-limiter in 6th, which (depending on your gearing) is unlikely isn't it? If I was reaching the rev-limiter in 6th, I'd be changing my diff to improve top speed. Edited by - charlie_pank on 2 Jun 2004 13:40:51 Edited by - charlie_pank on 2 Jun 2004 13:41:43 Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Surely t's much easier to just learn to remember which gear you're in than fit a sensor - especially given the trouble you're having! A squillion bikers manage, and presumably you would only reach for 7th when you reached the rev-limiter in 6th, which (depending on your gearing) is unlikely isn't it? If I was reaching the rev-limiter in 6th, I'd be changing my diff to improve top speed. Do you drive a bike-engined car? What you say is very much a case of easier said than done. Yes, I can get by by not having my gear displayed and, for the road, it's just fine. However, on the track it's very very easy to lose track of which gear you're in and a grab for 7th (which happens occasionally) or knocking down the wrong number of gears for a corner, lose time. Top speed is already 130mph and is just about limited by power (i.e. the rpm's are close to redline but not quite) so it's already geared perfectly. The issue is that there's still so much acceleration in 6th gear (11mph/1000rpm) that grabbing another gear feels right under certain circumstances (i.e. often on the road and sometimes on track). Having said all that, the challenge of getting this thing to work is all part of the appeal. Surely the various mini-projects associated with Seven ownership all add to the overall ownership experience? Also ... a squillion bikers also fit gear indicators Ian. Link to comment Share on other sites More sharing options...
Mike Molloy Posted June 2, 2004 Share Posted June 2, 2004 Even on a bike it's not that easy. I went from a 1200 Bandit (5 speed) to a Firestorm (6 speed, with 5th and 6th very close). I found I had to re-calibrate my left boot. Never totally sure I was in top without a confirmatory prod. A BEC is much worse due to the shorter overall gearing (the bike was geared for 160+ I'd guess). 115mph in 5th = 11000rpm. Change to 6th and it drops Having said that, my taste is obviously questionable based on the following... I got passed by "Saxo Dazza" on the m/way the other night, emitting an eerie blue glow from his "neonz" (sic). My first reaction was "hey, I gotta get me some of those!". Been trying to get a grip ever since. "Captain, we are leaking plasma from the starboard warp nacelle!" Have you solved the problem now then Ian? Link to comment Share on other sites More sharing options...
toys Posted June 2, 2004 Share Posted June 2, 2004 Ian, This isn't going to be too much help but I had the same problem on my Fireblade Seven when trying to get a Datatool Digi gear indicator hooked up. Again, I tried using the defunct bike speedo output (it seemed obvious which wires to use from the Haynes manual). No luck though - it just never seemed to 'catch' when going through the learning process. I have now got used to not having one and have removed it completely - a good shift light is all I seem to need on track. Several of my competitors do use this system though and have definitely made it work - it might be worth a post on www.bikecars.co.uk forum for advice... Mark Link to comment Share on other sites More sharing options...
Andrew Walker Posted June 2, 2004 Share Posted June 2, 2004 Ian T. I have been there big time on getting my Translogic gear indicator to work on my Cat-Fireblade. It's designed to be used on a bike so should be very easy - not I should have realised when the chap was trying to sell me the optional speed sensor. I was very keen to use the sensor built into the top of the gearbox, rather than add more sensors. It picked up the tacho signal no problem. It occured to us that the speed sensor needed powering up (I say 'us' because by this point an electronics expert friend had been brought in). Still no joy. The signal is incredibley weak. My electronics expert then brought in his "Boffin" with an oscilloscope. The 'boffin' took half a day to analys the signal and build a bespoke amplifier to go between the sensor and the Translogic unit. It now works fine on the track - and about 95% on the road as it has difficulty at slow speeds. I like the Translogic unit as it also has change-up lights built in and a manual lap timer. But what a pig to get it working. If I did it again I would just buy the optional speed sensor and be done. Sorry this doesn't really help you get your indicator working. Link to comment Share on other sites More sharing options...
charlie_pank Posted June 2, 2004 Share Posted June 2, 2004 Do you drive a bike-engined car? No, but I do ride a bike. If you don't like the car, I'll do you a swap for my K, cos I'd love a bec What you say is very much a case of easier said than done. Yes, I can get by by not having my gear displayed and, for the road, it's just fine. However, on the track it's very very easy to lose track of which gear you're in and a grab for 7th (which happens occasionally) or knocking down the wrong number of gears for a corner, lose time. -IMHO - it's normally about knocking down a number of gears relative to where you started ie - rather than saying "right now I need 2nd" I would say, "right, I need to be 3 gears lower than I am now". I do this both on track and on the road, in both car and on bike. Perhaps it is because my driving style of choice has me letting the clutch up between each gearchange.... Top speed is already 130mph and is just about limited by power (i.e. the rpm's are close to redline but not quite) so it's already geared perfectly. The issue is that there's still so much acceleration in 6th gear (11mph/1000rpm) that grabbing another gear feels right under certain circumstances (i.e. often on the road and sometimes on track). -Is this not about learning and throttle control rather than anything else? If it is ultimately limited by power, then you need a shift light instead. Having said all that, the challenge of getting this thing to work is all part of the appeal. Surely the various mini-projects associated with Seven ownership all add to the overall ownership experience? -Yup, can't fault you there. Each to his own etc... I hope you get it sorted to your satisfaction. Also ... a squillion bikers also fit gear indicators -500 of the 3500 KSIs on the road are bikers too ☹️, I wonder if that's cos they weren't good enough to know which gear they were in! 😬, were they too busy looking at the display of the gear indicator 😬! Seriously though, I don't consider myself to be a particularly good rider, but I think there's probably a better than random correllation between knowledge of current gear and riding ability. Edited by - charlie_pank on 2 Jun 2004 15:18:38 Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 toys, Mine seems to "catch" ok but only in the first 3 gears or so. I'm assuming the signal I get from the speed sensor is so weak that it's ok as long as the pulses are slow but once they speed up in the higher gears, the DG8 loses the plot. I've read a number of things that suggest the DG8 is much better than the Digi which might explain why you had no joy at all. Andrew, I've had some communication from Acumen who say that the standard bike speedo uses a shunt resistor to ground which (I assume) is responsible for somehow boosting the voltage from the 0.16V I get now to 5V. Having said that, I reckon a transistor-type arrangement would do the trick too. Your boffin doesn't live near Reading does he? lol Charlie, I do have a shift light and, to be honest, the gear indicator is a "nice to have". The real satisfaction now is going to be getting the bugger to work at all Ian. Link to comment Share on other sites More sharing options...
charlie_pank Posted June 2, 2004 Share Posted June 2, 2004 Viz top tip - a little whiteboard next to the gearstick with a horizontal line across the middle of it, you can keep a marker pen in your left hand. Don't write down the number you've changed to, cos that will take too long, just put a mark in the top half for "up" and a mark in the bottom half for down, do this each time you change gear. If you forget what gear your're in, just take a quick look at the board and tot up the number of marks in each area to work it out. 😬 Link to comment Share on other sites More sharing options...
Mike Molloy Posted June 2, 2004 Share Posted June 2, 2004 Ian, Will Acumen tell you what the input circuit to their product looks like? What signal format do they require to adequately drive it? If we knew that, I'm sure we could coax the sensor into producing something appropriate. Looking at their website there are no particular warnings about the CBR1100XX installation. If the signal from the sensor to the speedo was particularly weak, then breaking into the circuit and piggy-backing another load on to it would be likely to cause problems. I am surprised the required load resistor is from sensor output to ground, but I'll try and get a picture on my scope-meter tonight. Link to comment Share on other sites More sharing options...
toys Posted June 2, 2004 Share Posted June 2, 2004 Ian, Yup - like you it would only 'catch' in the first couple of gears. From the other posts here it does look like a weak speedo signal is to blame. I just wonder why it would be different in a car installation as opposed to the bike Link to comment Share on other sites More sharing options...
STEVE GILBERT Posted June 2, 2004 Share Posted June 2, 2004 I have the Digi which works OKish i.e not 100% on my Blade. It uses the proximity sensor on the propshaft bolt heads for speed and the pulse generator from the crank for the tacho Can you not shift the Stack Sensor to the rear wheels while you set it up? Steve See My Caterham Fireblade Here. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 I just wonder why it would be different in a car installation as opposed to the bike Based on something that Acumen have said to me (but they're being a bit slow clarifying) the bike speedometer does something to the signal that enhances it. Ian. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Steve, Yes, I'm thinking about doing that right now, lol. I'm praying there's a suitable bracket ... Ian. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 I've also been messing about with a universal amplifier module that I bought from Maplin just now. It's made a big difference (I've managed to train up to and including 4th gear which is two more gears than I've ever managed before) so I think I need to muck about with the input resistance to the amplifier a little bit. Mike ... still keen to know what results you manage to get tonight if you get the chance (thanks in advance). Ian. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Mike, You truly are a genius ... I wired a 16.8k resistor across pink and black and, hey presto, it learnt each gear in about 10 seconds and I completed the learning process in about 30 seconds flat 😬 No need for an amplifier either. Cheers matey ... Ian. Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 .... ah, so near yet so far, lol. Took the car out for a quick post-training test-drive and, at high revs, the gear indicator acts more like a speedo. Oops. Looks like the speed sensor connection is sorted but I'm now a bit suspicious about the tacho feed. I've tapped it from one of the low-tension wires going into one of the coils (as suggested by DG8 fitting guide) but the installation guide does say this connection may get a bit noisy. I'm going to try tapping into the bike tacho connection (if I can find it) or the crank sensor. Watch this space ... 😳 Ian. Edited by - IanT on 2 Jun 2004 20:25:14 Link to comment Share on other sites More sharing options...
STEVE GILBERT Posted June 2, 2004 Share Posted June 2, 2004 I tried this and it didn't work Go for the Pulse Generator feed to the ECU Steve See My Caterham Fireblade Here. Link to comment Share on other sites More sharing options...
Mike Molloy Posted June 2, 2004 Share Posted June 2, 2004 Ian, Just had a looksee at the signals, and the sensor is pretty much just a switch to ground. That means you do need a pull-up resistor of some sort. I used a 47K to 12V and got a nice 0 - 12V pulse train. Turning the prop by hand gave me approx. 10ms pulse widths, so I guess you'd be expecting quite a high frequency signal at full chat. You might have to go to a lower value pull-up - depends on the input impedance of the indicator module. Could do with more info on that. From what it says in Haynes, the Honda speedo only has a pull-up to 5V, but I don't think that makes any difference to us. The tacho feed on my engine is a yellow/green wire from the engine ECU. I found this lurking in the engine bay unused (the Stack tacho feed is taken from the LT side of one coil) so I poked it through a spare pin in the grey engine connector. Not sure what to do with it though. Maybe feed the ACES shiftlight? I haven't got the engine going at the moment (oil tank leak ☹️) si I can't check out the tacho signal. In general anthing to do with the coils is pretty noisy, so better to use the dedicated "clean" signal if you can. I'll be interested to hear how it goes when you get it working. Will you be able to see the display in bright sunshine? The $64000 question... Link to comment Share on other sites More sharing options...
IanT Posted June 2, 2004 Author Share Posted June 2, 2004 Mike, Yep, per previous post, I now have a 16.8k resistor across the +ve and sender output. Also have the tacho feed wired into the Yellow wire (not the White/Yellow) from the crank sensor (thanks Steve!) I've just been out for a drive and it is now perfect. If anything the unit was learning too quickly and I had to make sure I changed up quickly enough so that it didn't learn the same gear all over again. I think my total "time to train" was about 20 seconds, 200 yards and six very rapid gearchanges Your suggestion about the pull-up resistor and Steve's suggestion about using the crank sensor were the two things that have got this working ... thanks again to both of you. Now it's all functioning I'm very impressed with it indeed. Having read lots of stuff about some gear indicators reacting very slowly to gear changes and/or wandering between gears, I was pleasantly surprised to find it displays the new gear before my foot is even off the clutch pedal and doesn't get confused at any road speed or any rpm. Very cool indeed. Now I just need to work out where I'm going to mount the display ... Ian. Link to comment Share on other sites More sharing options...
STEVE GILBERT Posted June 3, 2004 Share Posted June 3, 2004 Right then Ian I'll go and re-wire mine to the Blade speed sensor instead of the poxy proximity sensor. Another for Blatchat Steve See My Caterham Fireblade Here. Link to comment Share on other sites More sharing options...
Blackbirdman Posted June 10, 2004 Share Posted June 10, 2004 Bit late spotting this thread. I fitted the DigiTools indicator and had no problems as it worked first time using the Stak wheel speed sensor. For ful details see my article in the next Low Flying 😬 Matt Is it a bike? Is it a car? No it's Blackbirdman Link to comment Share on other sites More sharing options...
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