IP2 Revcounter

[gripper]

Giving my bike a good beasting yesterday I noticed that the revcounter was climbing towards 5000 then dropping back, bike was still accelerating. Any ideas? (IP2 with digital ignition)

[commando-rotary]

Hi Dave, In all probability a loose connection i would go for the spade connecter on the coil that gives it the signal first. all the best D G.

[commando-rotary]

or corrosion in the multisocket under the console. D G

[Howell]

On the Interpol, the revcounter takes a pulse from one phase of the alternator - check for a good connection here,(a yellow wire I think) and check battery voltage with the bike running as this could also indicate a failing regulator.

[gripper]

Looks like that's not far from the measure of it. Bike was running fine, still exhibiting the same failing revcounter above 5000rpm. Yesterday revcounter quits completely, this morning very slow to crank but started, 10 miles to work, needed a bump start this evening, 14 miles home, engine dies 20 yards from home. (how jammy was that?) Battery showing 11.45 v Still running the sparkrite regulator. Can anybody recommend a replacement if it's shot?

[Richard Negus]

Dave,Before investing in a new regulator, better to identify the fault.As the tacho (if it says Made in France on the face) takes its signal from the alternator a/c, it may be that there's a fault there. Usual culprit is the cable where it exits the engine; although there's a protective strip, the flywheel can rub through that and then the wiring insulation. Do a resistance check across each pair of alternator wires to see if there's an odd one.If they're all equal, and no short to earth, then it's tacho fault. As a double check, take the flywheel cover off and have a squint at the cable and the stator windings.If the tacho says Made in Germany, then it's driven by the ignition output; as you have Startright digital, it may be a wire from one of the coil signal wires.Sounds more like a tacho fault though. If the alternator is ok, a simple voltage check with engine running will tell you if the regulator is, er, regulating.If you can dispense with the red warning light, then almost any Japanese/Chinese regulator will do the ; select one from a large-capacity bike, three a/c wires in, power and ground out. Electrex will sell you an expensive one, eBay will provide a cheaper option.R.

[gripper]

Thanks for that Richard. It is a french revcounter, looks pretty cheap and nasty but if it is u/s is there scope for a repair on the revcounter or is it a basket case? I will check out the alternator first.

[Richard Negus]

Dave,That'll be the Veglia, then. Made in France & fitted OE to all IP2's. The later Motometer, fitted OE to all Classics, was also retro-fitted to some IP2's when all Veglia stock had gone. A major change as it needed a new Sparkrite ignition unit as well.The Veglia is an odd one, the only tacho I know that senses alternator a/c. Someone must be able to repair it - Instrument Repair Service at Nottingham??Unless you particularly want a tacho with the 'Norton' logo and red band in the right place, why not look for one that's driven from the ignition, one pulse per rev - but not a Motometer, the numbers fall off , I believe.The F1 tacho is ignition-driven, made by Nippon Denso for the home market Yamaha FZR250RR screamer. Not much chance of finding one of those on eBay, but worth a look anyway.R.

[Richard Negus]

Dave,I,of course, meant Nippon Seiki!At Hinstock, there's a new NS tacho from a Bombardier two-stroke single. Probably one pulse per rev, red line is near enough, and possibly the correct diameter.R.

[rjg30091982]

Dave,My IP2 does exactly the same!Russ

[gripper]

The alternator is producing power but the Sparkrite regulator is burnt out. I've opened it up and there is a nasty smell and two of the transistors are burnt and the rest don't look too healthy. I suppose I could source some new transistors and replace them but I'm more inclined to fit a newer unit. I think the revcounter failing might just be coincidental as the feed to it comes direct from one of the alternator output wires, so the failed regulator should not have affected the revcounter. Or am I wrong on that? I can live without a revcounter for the time being, just need to find a regulator rectifier to get back on the road. Electrex do seem a bit pricey but it would be new and should have a warranty. Any thoughts?

[johnbirchjar]

Electrex do one for Commanders & F1s part No RR10 £66-00 (inc vat & p&p)not to steep a price.J.B.

[gripper]

Yes, I've gone for the Electrex jobbie. If the revcounter is toast I have a Honda NTV 650 one surplus I might be able to shoehorn into the casing. Would the signal for that come from one of the low tension coil wires Richard?

[Malc]

Richard,FZR 250 tacho, Have 3, but are attached to my bikes, These are the 2KR models that only rev to 17,000 not the 3LN models that rev to 18500. I like these little engines, both models produced 45 bhp but to get the 3LN model to rev higher, Yamaha fitted con rods 2mm longer and reduced the deck height but unfortunately, they became a little fragile. Were the clock faces changed or was the intention to get the F1 to rev a little higher?Malc

[Richard Negus]

Malc,The faces were changed to show the 'Norton ' logo on the tacho and the tacho scale reduced to suit the engine. Norton had to buy, I think, 200 sets at one go so there are still one of two complete in the ANIL stock.Dave,I don't know where the NTV takes it's tacho feed; if it had conventional 12 or 6 volt coils, then the tacho might well work. Select either black/white or black/yellow coil low tension signal wires for the tacho feed, but not from both or nothing will work.R.

[rustynuts]

Whilst on the subject of clocks, does anyone know if the classic speedo is a common part fitted to any other machines? I occasionally have thoughts about replacing the police speedo with something which fits in the instrument cluster.

[Richard Negus]

I believe Andover Norton have a small stock of the Veglia matching speedo (with 'Norton' logo).Original 'new' old parts which were meant for Aurora, predecessor of the Interpol 2, that didn't make it into production.Expensive and the last few are probably showing signs of their age (about 34 years!).The cable square and the cable thread is the same as Yamaha so a Nippon Seiki speedo may fit. A bit late to go out in the workshop tonight, but I think the cable turns per mile is printed on the Veglia speedo (1000?)R.

[Richard Negus]

I think the cable turns per mile is printed on the Veglia speedo (1000?)R.

The Veglia speed says "1000T = 1 mile".I think I've seen other brands of speedo showing slightly different, some below, some above.The Nippon Seiki Commander speedo is a bit coy on the subject.R.

[gripper]

Electrex regulator/rectifier fitted and charging restored and strangely the revcounter is working again. Odd seeing as the revcounter feed is direct from one of the alternator wires, ie before it gets to the regulator. Not sure if the revcounter works all the way to the higher revs as I was smoking the garage out and it's raining well. Full test later

[Howell]

The trouble is that most motorcycles have a permanent magnet alternator, and these are regulated by shorting thestator coils using thyristors controlled by output voltage. This is why the heat sinks are necessary. Good advice also, is never to jump start, or use a booster with such a system, as too much power can be dissapated causing failure. I believe Frank Westworth has recently found this out the hard way! Should a thyristor go short circuit, that coil will output nothing - hence the revcounter issue.Regards,Howell

[Howell]

Sorry, I should have said never jump start from a car.

[Richard Negus]

One of the joys of running an air-cooled is that I now get to experience first-hand what I've been reading about for years - the epileptic Veglia tacho. Mine does it too, or at least it stutters at 5,000'ish, falls back, and then continues normally.So if I change the regulator, all should be well?R.

[Howell]

Hi Richard,No doubt you have experienced far more of these problems than I have, and I wouldn't contradict anything you have to say on any rotary related matter of course. However in 1996, my Interpol showed the same symptoms and was cured by replacing the, by then, toasted sparkright unit with a Boyer powerbox. Touching a large piece of wood, I can say the tacho has behaved fine since. I thought, bearing in mind Mr Westworth's problems it would be worth telling people about the shortcomings of what is , electrically, a crude means of regulation. Cured by you of course, with the "Jam sandwhich" by installing a car type wound rotor alternator with excitation control.I should have said also that jump starting from a car is fine as long as you don't do it with the engine running, as is normal if you jump start another car!

[Richard Negus]

Hi Howell,Thanks for the info.Yes, experienced lot's of 'faulty tachos', but never got to the bottom of the fault.In the short term, I'll fit the Commander Kokusan regulator (when I find it - just moved house and workshop) and ignore the lack of a warning light.In the long term, I have another similar NipponDenso generator to integrate with the reverse-flow system. A project for next Winter.R.

[gripper]

Thanks for the info on regulators. I can safely say the thyristors in my Sparkrite box were toast. Is it worth replacing these thyristors for use as a spare? They seem simple enough to replace and what would be a modern replacement be? any electronic experts out there?

[Howell]

Pleased to help if I can. gripper, repairing a 20+ year old PCB is fraught with issues - throw it in the bin! It seems that Reg. failure is common in the motorcycle world, and has caused a lot of bad press for some time. (bearing in mind the potential for actually causing failure by jump starting etc).I have just replaced the unit on my Commander as well, moving it to to replace the LH battery to aid cooling. I also have a speed triple and perusing the Speed Triple forum has revealed that they too suffer. Good News time though! The site Moderator "DEcosse" has posted an excellent article about these issues, and pointed out that an electrically superior regulator now exists, which is based on MOSFET technology, and does not dump lots of power to ground through the thyristors and heat sink. The magic part is the Shindengen FH12AA, and is fitted to current superbikes including '07 on Yam R1, '06 on FJR. You can find this article if you access the site and search "Voltage Regulator". To go off thread a bit, I hope your moves have gone well Richard; it seems you have enough to keep you busy. Did you manage to track down a Commander after? or is the air-cooled one your replacement project? The history of the reverse flow system would be of interest to many people I suspect, including me. I understand lower runnning temp, and improved main bearing live was the result. Can you add any info? A related issue - Why is the aircooled engine such a bitch when cold compared to the water cooled unit?Regards,Howell

[Richard Negus]

Howell,Very interesting! Where would we be without forums? Now, do you have a way of working the alternator warning light? I fitted a Commando simulator to F's IP2, sensing alternator a/c, and he says it didn't bring the light on when his regulator failed. I wonder how it works on a Commando?The air-cooled is my project, although I've got used to bimbling round the lanes and might not change it as much as I'd originally planned. The above IP2 is ex-City of London and reverse-flow and is certainly 'softer' than the average IP2. I'll try to do one that is less restrictive in the induction plumbing. The first prototypes had really tortuous bends in the pipework and lost a lot of power, all to accommodate the front engine mounts. City had four IP2s and, I think, two of them were converted to reverse flow in an attempt to make them survive. It'll be interesting to see if the other one turns up sometime soon, Russ.I think air-cooleds take longer to warm up because of the amount of aluminium in the plates and housings. Commanders circulate water around the engine only until the thermostat opens, promoting a quicker warm-up as heat isn't dissipated to the airflow. Whilst air-cooleds typically have lower compression ratios (8.6 or 7.5 vs 9.0) everything else is the same, so they should perform the same.R.

[Howell]

Richard,The thing is, the bloody thing can fail in different ways. The Regulating thyristors precede the rectifying stage, so overvoltage is just as likely as under voltage.The Commando used a Zener diode as a current dump AFTER the rectifier, (Even cruder) but often failed short circuit, so took the main fuse. I would suggest either fitting a voltmeter, or one of the new fangled LED voltage indicating devices as sold , I see by Paul Goff amongst others for around £25. Something else to watch and worry about!By the way, I have perversely kept the original alternator on my Commander while fitting the "DaviesCraig" water pump. Actually, it was this that indicated overvoltage (found to be 16.6V on a meter!) and led to me replacing the regulator, I just wished I had come across the info. sooner, as I would have gone for one of the improved types.Is it a major job to convert a Aircooled motor to reverse flow? how about the oil feed pipes - which I assume have to go to the main bearing housings? And crucially here, without the benefit of a fairing to hide everything, what is the appearance like? Regards,Howell

[gripper]

Try ebay and gammatronix for a good LED battery condition monitor, less than £10 inc p&p Now my Electrex reglator is fitted and the ign warning light is gone, I'll be fitting one in place of the original warning light. I've been toying with replacing the piddly little warning lights with LED's too, but of course being +ve -ve sensitive it could take some time.

[Ian]

Have I missed something? What is a DaviesCraig water pump and does it get rid of that permanently troublesome Oldham coupling? If so, I want one! Most of my time on the bike recently has been spent on that special part...