NE0

(posted earlier) More news.... Still not had to externally recharge the battery which means its still on the original charge. This proves the battery is being charged quite happily on the charging circuit. remember I ride with all the lights on day and night! Anyway, just to let you know I've sourced a 12v 45w/45w bulb same design as the 6v one with the 3 holes in the flange from good ol' ebay. Look for APF Bulb 12v 45/45w its a lot brighter than the 35w, and is at maximum brightness above 3500revs. Not saying it lights up the whole street but an improvement all the same. I've taken off the fiamm air horn as I think the 6volt horn (i never upgraded that part) sounds much louder with 12v supply...don't worry it can cope with it. NE0

Hi Stiggy, A warm welcome to you (Suns been shining all day on Brighton) Just along the road myself from Brighton around the Portslade area. If you're into older bikes you might have seen me around on mine

OMG the producer of the video needs a course in how to edit! Made my eyes go funny, all the chops and repeats, he must be on drugs!!! OR I must be getting old..........

Trouble is I've got nothing to compare it to OG Its not that heavy, must be aluminium, so its likely to be aftermarket. I've not got all the receipts for work done so I don't know when it was replaced. I've seen the wadding available at yambits OG, is one pack enough? does it compress?

OG I can only assume its OEM. The bikes only done 19000 from new and there are many receipts for work done. Exhaust pipe welded on 3 occasions match the 3 small patches on the bend...just where its got a hole now! No mention of a new tail can. The can is a smooth black cylinder with 3 allen screws which hold the end cap on. No numbers visible? The wadding inside just falls apart when pulled. Its oily and black as expected. I've got a spare exhaust chamber for the front to fit on, (needs a gasket and connecting rubber first) I assume replacing the wadding will effect the noise level.... just trying to comply with Mr plod ..........and my neighbours i guess!!!

I was waitng at the lights today and a PC came over and tapped me on the shoulder.. 'ello, ello...your bikes a bit too noisy!! Eh?, I couldn't hear him...my bikes a bit noisy! my helmet helps drown most of it! Anyway, he was alright about it, but he said I ought to get it a bit quieter! So once i got it home I set about having a look...and listen. With my helmet off, clearly it is a bit on the loud side..... However, it doesn't help that the rubber joining the rear can is a bit perished and loose. Plus there's a small hole in the bend by the engine...have to get the welder out! I also discovered the wool inside the rear can is a bit flakey and jet black! Looking on ebay I see you can get replacement baffle wool, and hopefully a new rubber connector. But I also came across decibel killers... Can they be fitted to the DT can? Will repacking the baffle wool cure it on its own? I've not had to worry about this sort of thing before my 400/4 just purrs....

E stands for EARTH F stands for FIELD I is for IGNITION / LIGHTS Regulators protect lights and stop batteries from frying.

This is a common regulator fitted to many japanese bikes of the 70's My Honda 400/4 has an identical one and so did my other Hondas. It's called a Pointless regulator in that its solid state, no moving parts! The colour code is GREEN for EARTH , WHITE to the ALTERNATOR and BLACK from the LIGHTS Circuit. As long as you connect your EARTH (whatever colour YOURS is) to the GREEN terminal you won't go far wrong. If you're interested it opens and closes rapidly inside which creates a resistance in the alternator field coil thereby reducing its output...stops your lights blowing! Hope this helps.

Or If you're mad..........try this

Just to update you on the success of Project firefly! It's been a month now since I did the conversion. No bulbs blown and there has been no need to externally charge the battery. I ride with the lights ON all the time I've done a total of 190miles, so theres been a constant draw from the battery, including using the indicators all the time (No green laning). The timing and CDI was untouched. Everything works fine......... a worthwhile upgrade to 12volts.

Hi Aaron and welcome, I'm sure this is not as uncommon as it appears.... Bikes and cars are all manufactured for different markets. A european bike will likely have a european wiring loom installed, but local variations to indicators and switches will be added to depending on its final destination. I'm sure the US market is similar. It's likely that your bike has a US loom and it would have been suitable for either US or canada etc. yes? If the wire ends in the plug then another plug with different wires connected could be plugged in to complete the bike. You say the diagram shows the wire and is supposed to be like that, but have you checked the wiring diagram for other countries? I bet somewhere you'll find the wire is used. It's easier for Yamaha to fit one loom than have several variants. In terms of japanese efficiency would they have installed the loom and removed the fuse if it wasn't going to be used later, or simply install the common loom and then install the next loom on the next bike and so on, regardless of its final destination? my feeling is its just one of those production issues and nothing more. After all, my car has all the complete wiring for cruise control, but the clutch and brake switches are missing, even though it has the fuse.

Snap! Mines a wine red one, its a very nice fit and I'm very pleased, I bought mine last year when they had the sale on and it was well under £180...not that you want to hear that! see I told you it was bloody good service...they really are the dogs dangly bits. well recommended. (what colour did you get?)

Good to hear you've got a new MOT on your machine. I therefore assume you sorted all your starting problems out. You started a couple of threads in the workshop area but never finished them off to let us know what the problem was Starting Problem and Overflow problem One thing that really gets my goat on ANY forum is reading threads that never tell the audience how they solved the problem. New members will read posts and think, 'thats whats happening to my bike...." but never find out the actual cause, especially when there are multiple solutions. It only takes a couple of lines... Thanks guys you were right, or nope turned out to be a damaged monkey reciprocating lubricating screw!....or whatever thats it..moan over! Well done for the new MOT

I'm not far from you Jams I too went to bikes and it was the same then, its all to do with them spending time with you sizing you up and then the customer goes off and buys it online cheaper. So its a valid point. I also tried Cissbury leathers just outside of Worthing and Alfs in Worthing both let me try on helmets no problem, but they didn't have the colour I was after. I ended up at Helmet City just the other side of Crawley/M25 area,bit of a drive , but I tied it in with taking the children to the small zoo there. I tell you... bloody good service. Highly recommended. Hundreds of helmets, all colours all sizes and all in stock. Well worth the visit. I got a Shoei raid2 to match the colour of my 400/4.

So I guess a 'thank you' would be in order.

Invaribly fuel coming out of the overflow is caused by the float 'stuck' in the down position allowing fuel into the carb from the tank. My 400/4 has 4 carbs and one occasionaly tends to stick after I've stopped. But its a bugger to get at so it will have to wait until they really need to come off! keeping the petrol tap turned off after stopping solves the problem. (it only happened about twice last year hardly regular but I know the cause) In your case stale petrol may well have gummed up the float pivot, or the float axle part. I did say in your previous post cleaning all the fuel lines and ways is essential.I also noted that your earlier problem was caused by I don't think you cleaned it enough. As Paul says don't try correcting problems when its caused somewhere else and often the simplist explanations are the main cause. I think you really need to clean everything inside and out. A carb strip down is just that, you strip it right down to its component parts and clean everything. If there's one bit of crud on the axle pivot the float will stick and you will have problems. Every little nook and cranny needs to be so clean that you'd be confident you could it your dinner off it!!

Expecting a bike to start after a few years of storage is a bit optimistic. Its surprising how the damp penetrates everything and old petrol literally gums up the works! Over time stale petrol will lose its ginger and if left in carbs even for a few months it starts to coat the workings with a shellac type varnish. Its a bugger to get off but cleaning all the fuel lines and ways is essential. Spark plugs seem to absorb damp, and so does the HT side of things. Spraying WD40 over everything does help, but I'm afraid if its been a few years since it last started you've got a bit of work to do. However, stick to it once you've got her all cleaned and dry with new petrol, you stand a better chance of starting the ol' girl....

Part 6 Avoiding the Big bang How to connect it all up Changing over to 12volt is hassle free, There is no need to cut any wires of the original loom, so if you don't like it or you're not happy reverting back to 6volt is easy. Don’t be tempted to install the battery first then turn the lights on! its not a good idea as all your 6volt bulbs won't last very long! Changing all the bulbs is clearly straight forward and obviously should be done first! The indicator flasher unit needs to be replaced along with the bulbs, (I did try seeing what would happen with the 6v one still attached but it flashed far to slowly,) The flasher needs to have the two pins at right angles, and rated at 12v 18w~23w. A suitable one is a universal type WRE04 and comes with the rubber mount. The combined regulator/ rectifier used is from a HONDA C90 cub G model 4 pin version suitable for a late 80’s. bike. SH570-12 / 6.7 011 I mounted mine next to the indicator flasher so the wires from the original rectifier attached directly. The C90 regulator has a separate earth tag so does not need to have the body in direct contact with the frame, so for the moment I just secured it with a couple of cable ties. Once you’ve secured the reg/rec then unplug the old 6v rectifier and plug them into the positions in the diagram. The C90 reg has all 4 Lucar male spade terminals. My old 6v rectifier has a male and a female connector, If you want to keep the option of returning the bike back to 6v, don’t cut the male spade off just make up a short female to female connector to connect the wire from the rectifier to the new one. Disconnect the old 6v regulator and run a new length of wire from that connector in the loom to the New reg/rect as shown. Finally connect another length of wire as an earth lead and find a suitable Earthing point. As I fitted the new reg/rec next to the indicator flasher, the lead can connect to the common earth under the HT coil. The Main headlight will now run off the generator. The rest of the lights and horn will, as before, run off the battery. Only this time it’s 12volt. That's it! Simple! If it doesn't work out for you, you can swap it all back to 6volt. No cut wires. I'll report back on the success of project "Firefly" soon. So far everything works perfectly. Not had to externally recharge the battery. Hope you enjoyed the posting its taken quite a few hours to write it all up. References: Yamaha Haynes workshop manual 210 ISBN185010 3003 Mastering Electronics john Watson ISBN 0333 408233 Hillier's Fundamentals of Automotive Electronics V Hillier ISBN 0748726950 Automobile Electrical and Electronic Systems ISBN: 0750662190 Yamaha club forum, Honda C90 website, Remember this is a 12v conversion for a 1978/79 DT 175 MX UK 2K4 and 2X2 models. I’ve also checked the Haynes wiring Diagrams for UK 4J4 which is compatible. Yours may be different and may require additional research before converting

Part 6 contains all about the regulator, should be done before the weekends out....

Part 5 What needs to be changed and how much will it cost! The biggest stumbling block in the past is trying to source a 12volt battery small enough to fit in the same space as the 6volt one. Well, good news folks, there is one…hurray! Battery codes are : YB3L or FB3L or CB3L The dimensions are: Length 98mm Width 56mm Height 110mm (the 6volt one is 6N6-3B-1 : 99mm x 57mm x 111mm) These 12v batts are listed for: Cagiva 350cc T4R (1987-90) Fantic Motor 125cc Raider LC Fantic Motor 250cc Raider LC Honda LS110 TH (1989-92) Honda CG125 -IR (1992) Honda MTX125 RW RW-TH (1985-90) Honda NZ125 (1993) Honda NSR150 R R2 (1994-98) Honda MTX200 RW (1985) Honda XL200R (1983-1984) Honda XL250 R (1984-87) Honda XL250 RC (1982-83) Honda XL250R (1982-87) Honda XL350R XR350R (1984-87) Honda XL500R (1982-87) Honda CRM50 (1993-94) Honda MBX50 FW FWD S SD SWD (1985-87) Honda MTX50 FR RS S (1985-89) Honda NS50F NS 1 (1990-99) Honda NSR50 A F (1987-95) Honda XL600 R (1983-87) Honda CRM75 MTX75R (1989-94) Honda MBX75 FW (1983) Honda NSR75 (1992-1994) Honda MBX80 SW SWD 2 FWD (1985-87) Honda MCX80 S (1983) Honda MTX80 R2 RS (1987) Kawasaki KDX125 A1-A4 SR (1994-95) Kawasaki KDX125 B1-B4 Kawasaki KDX200 B1-B2 (1984-92) Kawasaki KH125 K7 - K10 Malagutti Runner VS Rally (1987-90) MBK 50 X-Limit DT50 (1997) Yamaha DT50 R (1989-1997) Yamaha V100 (1993-94) Yamaha DT125 LC (1984-87) Yamaha DT125 RE (1988-96) Yamaha RX150 (1995) Yamaha DT200 RE (1993) Yamaha SDR200 Yamaha XT250 (1984) Yamaha XT350 H N (1985-00) Yamaha XT500 (1986-89) Yamaha DT80 LC LC II (1983-96) Yamaha RD80 LC II (1983-86 I used the AGM Motobatt gel battery MB3U order code ASIN: B004EE2I62 available from Mad4bikes via Amazon.co.uk (cheaper than ebay) £19.99 (02/2011) The conversion will require: 12 volt battery (see sbove) 4 x indicator bulbs 12v/21w 1x tail/stop bulb 12v 21/5w 1 headlight bulb 12v/35w 1 pilot bulb 6 x dash bulbs (oil. Neutral etc) 1 x 12v flasher unit 1 x 12v Combined Regulator/rectifier 2 lengths of wire and connectors I already had all the bulbs from my car spares and box of bits kept over the years. I had to purchase the battery £19.99 and the flasher unit £3.50 from the local car accessory shop. The 3 hole headlight bulb came from a buy it now on ebay for £1.75. The regulator was on ebay for £4.99 no one else bid! New ones can be obtained for about £15. Postage was free on the battery! The cost to me was under £30 and most of this was the battery! If your aging 6v battery needs replacing then for a little more expense you might want to consider the conversion…… Part 6 next how to wire it into the DTMX

Am I not winning you over? I wasn't able to buy a headlight bulb in anything higher than a 35w one. But the taillight is noticeably brighter and at higher speed the headlight,I must confess, does look brighter to me. However, I think the upgrade aspect for me comes from having a 12 volt battery to deliver much brighter indicators a brighter brakelight and a more powerfull horn. You can't run an airhorn off 6 volt. If the car user can see my intentions and the pedestrians move when they hear the horn, then surely its got to be worth it?

Part4a That little coil beavering away! The measurement for Power in electricity is the WATT. that little coil produces 0 to 20v plus on the charge circuit and 0 to 16v on the lighting coil On the 6v original system the Bulbs on the lighting circuit Headlight and 3 instrument lights all add up to 45.2 Watts (The indicators,flasher unit,tail/brake,pilot,neutral,oil,indicator telltale and horn all run off the battery) The total wattage is 35w +10.2w = 45.2Watts (3.5w x3 =10.2 main beam tell tale + 2 x instruments lights) Thats the POWER of Watts the lights use, its probably not the limit of the wattage the coil produces If we replace all the bulbs with the same wattage but in 12volts the wattage remains the same, its still 45.2Watts the total AMPS used by the 6volt system is 7.5Amps (45.2w/6v) (Amps=Watts divided by Volts) the total Amps when its 12volts will be 3.7Amps (45.2w/12v) The difference is the coil produces 6 volts at low revs but generates over 20 at high revs. To produce 12volts at low revs there needs to be more windings the Watts output may well be lots more but the lights will still only uses 45.2watts maximum I think I know what your concerned about but its the Watts which are the key. If you turn on two 60watt bulbs indoors you still use 240volts but consume 120watts of Power. you don't have 480volts going through the mains. Does this help? I'm busy writing the next few parts....Its almost exciting isn't it?

Oooops I must confess my knowledge is a bit limited on the various models. My research comes form the forum and the ol' Haynes manual. I've corrected my posts to reflect this.

Part4 Any other options? My original inspiration came from the post about fitting the Honda C90 stator plate and CDi unit as a whole into the DT. The way it is described suggests you have to sacrifice your flywheel to obtain the collar part to fit the C90 flywheel onto. The two flywheels fit but are not aligned with the woodruff key and the timing needs to been adjusted. Swapping the entire stator plate means you also sacrifice the DTs own CDI unit which works fine as it is, You have the potential to lose the power of the spark at high revs, which is why my DT has 2 source coils for this. The other concern is on the DT the pulser coil is on the inside of the circle so to speak, on the C90 the pulser is on the outer circle and will only fit in one position in the crank cover, hence the reason why the timing needs to be adjusted as its all slightly misaligned. Going by the original poster he got his DT working with this set up, but he never got back to us to tell us how successful it actual was. Anyway I don’t want to replace the CDI unit on the DT the set up works just fine. It’s the lights which are the problem. The potential good news is if you really want to swap the 6v lighting coil for a 12volt one, the C90 is 12 volt and the unit on the whole is the same size as the DT, which means the lighting coil may fit providing the magnets of the DT flywheel give it clearance and the fixing holes are the same. The other promising part is that the C90 has a large following and many alternative hybrids utilise the C90 engine. Which means new dirt bike stators to go on C90 based engines are easily available and they are all 12 volts, including the lighting coil. Even better they are all under £20 new. However, I kept the 6 volt lighting coil, because of its power output as seen in the photos. Which also means you don’t need to worry about removing the flywheel, well not today anyway! Still interested? Part 5 shows the parts needed to make the 12v conversion,

Don't shut up mate, but the regulator is involved in the charging circuit. Part 3b The Regulator As you can see from photos the white wire output (charging coil) is over 6volt in fact it goes well over 25 volts, what stops this increased volts frying your battery as you ride? the regulator. On the 6volt regulator, it clips the volt to 6 volt, in your words its acts as a soak, which is probably a better description it certainly gets warm which is why it has those cooling fins, but it has an internal threashold which means, it 'soaks up everything above 6volt. Take a look at the wiring diagram of the DT and the internal switch arrangements. [from generator:- Lighting circuit yellow wire:charging circuit white wire] In position 1 on the ignition switch, (engine run on lights off) the white wire from the generator goes to the switch and is connected to the yellow/white wire to the regulator. In essence soaking up the excess volts which would fry the battery. In position 2 (engine run, lights on) the yellow wire from the generator is switched to the yellow/white wire to the regulator. The tail light and pilotlight (parking light) are both on drawing current from the battery. Switch the headlight on, the regulator 'soaks up' the excess current, in essence, and you're right, stopping the bulbs blowing. This 'draw' on the circuit causes the field in the generator (remember its the same coil) to partly collapse, thereby reducing the output from the white wire which prevents the battery frying. Elementary physics? or have I turned into brian cox! Here's a simplified diagram from later on in this thread, brought forward here to show the connections. The block shows the connections within the ignition switch making up the circuits in the various key positions of I, II, III.