Hi all, OK, am offering myself up for muppet of the month award as looking back I should have thouhght longer and harder about things but: I recently had my ECU die so bit the bullet and replaced it with a Nemesis ecu (which has made a night and day difference to the bike), then one morning the battery was dead, on investigation it was bloated and old so I bought a new one. All was good until last weekend. On a run (after about 140 miles) I made fuel stop and after filling the bike up I had no ignition lights and a nasty burning smell. I took the right hand fairing off to find my new sealed battery smoking and red hot. The AA man used a battery pack to get the bike started and the battery had 16.7V going into it at tickover! So clearly the regulator is chuffed. OK so I got a new regulator from Electrex along with extension cables to move it away from the header pipes as I think that is a real contributory factor in premature regulator death. Need to pick up another new battery but I am thinking that the regulator may not have been responsible for the ecu failure but almost certainly was what killed the other battery, so is there anything else I need to check before I fit the new battery and regulator? Any advice greatfully received. Fugly
you are totally correct when you say the regulator isn't necessarily at fault, although it often gets the blame. It's often resistance and/or corrosion in associated leads and connectors that's built up to a level that prevents the regulator performing as it should. One of the most common scenarios as a result is that the Regulator is convinced that it needs to supply more than is actually necessary hence the overcharging of the battery and often tell-tale signs of stripped paint on the frame. I don't know what bike you actually have but if it's 748/9** then it's well documented on here. If you can't find any links or specific help and/or 'Denzil' doesn't pick up on this thread then please p.m. me.
I checked all the contacts a couple of moths back and there was no corrosion on them so just re-vasalined them and put them back together. The bike is an 02 998S, I am just concious that I may not have got to the root cause and batteries are getting expensive ;o) Thanks for your input
if you feel sure that all leads and connections are ok and you still want to change from standard spec then I would thoroughly recommend that you go the Shindengen Mosfet route. These units perform more efficiently and run much cooler. Main problem is lack of availabilty new in the UK (I have tried contacting Yamaha UK etc several times). They are fitted to many of the big Japanese bikes but more common on American-spec models. There are several versions that are suitable but the later fitted types are the best choice (from memory only :- FH008, FH010, FH012 - AA). I used to have a link to testimonials/fitting guides but can't find just now.
Fugli, as Chris has suggested I had a regulator fail on mine (02 748s with the later 3 phase alternator - same system as yours) it ended up with 19v at tick over and melted a hole in the battery case which made me realise why AGM batteries were such a good idea, the acid loss and resulting damage was minimal. The failure occurred within a week or two of a dyno run and I think the reg let go primarily due to a slight and gradually increasing resistance at the plug on the three yellow wires which was compounded by the undissipated heat during the dyno run. When the dyno run was done I don't think the reg was cooled properly (with a well positioned fan). The regulator/rectifier failed short circuit and ran away leading to the over voltage - I may have been fortunate but despite driving the bike for 200 miles in this state no apparent damage occurred to the ecu. The only indication of it going was a slight eggy smell from the battery, also its final failure occurred after a 150 mile drive. Since then I fitted a new electrex regulator and decent quality AGM battery and soldered the three wires to eliminate resistance at the plug. However before soldering the wires I checked the resistance across the new plug(s) and got 0.5ohms on each of the three pins which if you do the maths has the effect of quite a heavy load on the alternator. Also the new regulator was getting quite hot and the three yellow wires were also getting very warm either side of the plug so I fitted a much larger heat sink, although this did not make it run any cooler. Since soldering the wires the regulator only ever gets warm and has never got as hot as it did with the connectors. I have also fitted an acurate digital voltmeter across the battery and can see exactly what is happening at all revs whilst driving the bike. The voltage with the engine running at normal revs is pretty static around 14v with fluctuations below 2000rpm between 12.9 and 14.6 depending on the engine temperature, engine speed and distance covered. I would fit the the reg/rec with a new agm battery and either replace the connectors with heavy duty clamping ones or solder the three yellow wires then heat shrink insulate them. Then check the voltages and see if the regulator and wires get hot to the touch - if it only ever gets warm and the voltages are similar to those I mentioned previously your problem is probably solved. I think moving the reg rec can only help but I don't think it is necessary if the connections in the wires are as resistance free as possible. Also contrary to internet lore the three wires are adequate for the job as fitted by Ducati/Shindengen and Electrex (people who say this do not understand three phase AC theory) but only if the connections have very low to no resistance. Finally don't forget to fully charge the new battery before you fit it. Good luck with this, since soldering mine the reg has run predictably cool even in traffic and the voltages always sit around 14v ( within 0.2v) during normal driving over 2k rpm
Hi Denzil, Many thanks for your detailed response. I had checked the contacts about two months ago and there was no signs of corrosion so gave them a fresh coat of vaseline to protect them (have palyed corroded alternator connector issues with a monster) and put it all back together. So you are saying that heat from the header in your opinion isn't an issue? The bike is at my parents so will be taking the parts there to fit and ride home so have not had a chance to look at mounting the regulator anywhere else as yet but was hoping to get in under the seat as there is plenty of air volume and heat from the cans isn't that high. Hopefully the Electrex unit will cure my problems once and for all but the voltmeter idea is a good one. Once again many thanks Fugly
Fugli, the heat from the header won't help, but IMHO it is not main reason why they fail. If you are interested this is what I did with mine using a heat sink and conductive paste from Maplins. Although this is with a Ducati OEM reg fitted. In the second you can see some of the damage to the battery box and acid staining on the cases is evident on both. If the battery that ended up with a hole had of been a normal lead acid one instead of the original 7 year old OEM AGM lead acid one it would have done serious damage. The voltmeter (EMV 1200 IIRC) was fitted just below the temp gauge on a couple of small blobs of blu tac and wired to the battery posts, if you use one of them they need wrapping in a clear waterproof film as the case is not waterproof.
£22 plus vat fom RS Buy Digital Panel Voltmeters 3 digit 2 wire signal powered voltmeter Lascar EMV 1200 online from RS for next day delivery. Good idea, thanks Denzil.
Pete, FWIW I also got some plugs that match the fused optimate connection lead (they are common on RC models apparently) and use that for the connection point to the meter as I was a little worried about it not having a fused connection. The short wires coming from the meter are soldered and heat shrink tube insulated to a two core wire which follows the RHS loom ending up next to the breather assembly (where I put the optimate lead plug).
I got the feeling that heat only kills the reg/rec when the bike is used a lot in stop/start traffic. I took my 748 on an Egg run a few years back and i suspect that killed the reg/rec on mine.
This is what I have fitted to my 748 and it works brilliantly. 12v Battery Charge Warning Light, voltage indicator | eBay Steve
I have just fitted one of those to my bike. I get a nice green...Until I put the headlight on...(HID) then flashy, flashy! One once else have this that has an HID? Or do I need to start hunting for a new rec? Cheers.
I had the same problem at first, it really depends where you connect the LED to in the first place, when you switch the HID lights on check the voltage at the battery, it may be OK, when I fitted my LED I had to change the connections a couple of times because of vault-age drop in the cables which gave a false reading. I finally fitted a relay directly from the battery which was switched by a wire from the fuse box when the ignition was turned on, it now works perfectly. Steve
I'm getting 13.6V at tick over which drops slightly when revs are increased. I tried a new rec/reg and no change. Anyone know what the amp out put from the rec should be idle? Cheers
The main wires for the battery warning light should be wired to the battery posts and the third one wired on the bike side of something like the + horn supply on a 998 (fuse 7 IIRC) or on a 748/996 to the RH switchgear run/kill switch +. However ideally it should be spliced to these feeds close to the fuse box. Nelson, the current output of the reg/rec is dependant on what is switched on and the charge state of the battery so is not a very good indicator to test for. FWIW I have a HID low beam and it uses less power than the 55w H3 bulb it replaced and has no significant effect on the voltage across the battery with the engine running except at slow tick over when the engine is warming up
Thanks Denz, I have got better results re-routing the reg feed directly to the batt. Need a better place for the live feed for the batt indicator as it's still border line... Horn+ feed did the trick
