NEV Posted June 8, 2011 Share Posted June 8, 2011 Just had a seed of a thought, and it is just a crazy idea at this stage, but, and OG I'm hoping for some input from you mate, along with others, But have had a thought about using my oil pump cable, (as it will be redundant as I'll be going pre-mix,) for operating the powervalve, mines a manual one at the min, I can only have it on two settings, locked open, and locked shut and although the cables and pulleys are easy enough to get hold of, the servo's aren't, and that depends if it's a 3 wire or a 5 wire one, plus they inna cheap. Has anybody any knowledge of this being done, and if not, do ya reckon it would work? Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 8, 2011 Moderator Share Posted June 8, 2011 Just had a seed of a thought, and it is just a crazy idea at this stage, but, and OG I'm hoping for some input from you mate, along with others, But have had a thought about using my oil pump cable, (as it will be redundant as I'll be going pre-mix,) for operating the powervalve, mines a manual one at the min, I can only have it on two settings, locked open, and locked shut and although the cables and pulleys are easy enough to get hold of, the servo's aren't, and that depends if it's a 3 wire or a 5 wire one, plus they inna cheap. Has anybody any knowledge of this being done, and if not, do ya reckon it would work? Back in the stone age as a snotty teen the new powervalve motors were just appearing. We were using parts from 350 power valves and good old fashioned choke cables (ask your dad) to opperate the valve manually. The 350 donated the pully/cable assy that fits to the barrel as the early learner legal powervalve stuff didn't have it. I remember one flash twat making an electric controller for his college electronics practical, worked too. It was basic and you can only realistically get low middle and flat out but it does work. The only thing you won't have is any electronic help as obviously the electronics ain't there. Didn't stop the last of the RD125's with the pv motor or the early TZR's from flying though. Link to comment Share on other sites More sharing options...
NEV Posted June 8, 2011 Author Share Posted June 8, 2011 Back in the stone age as a snotty teen the new powervalve motors were just appearing. We were using parts from 350 power valves and good old fashioned choke cables (ask your dad) Ask him about powervalves? lol the only motorbike talk I get out of him, is how he wishes he'd kept his Ariel square 4, mind you he is knocking on for 80, bless him, no seriously mind, cheers for the info Cynic, I was thinking of somehow going push, pull throttle, Link to comment Share on other sites More sharing options...
BEng Posted June 8, 2011 Share Posted June 8, 2011 About 20 years ago, when I had my first dt125, the last model before the dt125r, C Reg I believe. I was thinking of trying to do something similar to what Cynic suggested, but never got around to it. I just opened the power valve full and left it like that. If you used your old oil pump cable, it would not work quite right. As you only want the power valve to open when the revs are more then 7k. If it was connected to your throttle and at low revs say 4k you give it full throttle the power valve would open fully and the engine would bog down a bit and not accelerate as hard as it should because it would have to much exhaust valve timing. Then when it got to 7k it would start going like an idiot. I was thinking of using a throttle cable and lever from an old lawn mower, and mounting it on the left hand side handlebar. Then connecting the cable to the pulley on the power valve, then on the other side of the pulley connecting a spring which is man enough to pulley the back closed, but not to strong that it would pull the lever closed. The pulley would need to have some stops on it so it could only move from closed to fully open and no more. So it wouldn't be a 2 minute job. So what you would have is an extra lever on the left handlebar which you operate with your left thumb. When the lever is shut the power valve is closed and when you push the lever open the power valve would be fully open. The way I would envisage it working would be when you were riding around town or didn't need the extra power you would close the lever and this would give you loads of bottom end and a nice and easy bike to ride at slow to medium speed. Then when you want the power you open the throttle full, the engine would rev up (in gear I'm talking now, not in neutral), then at say 7k you would push open the power valve level. This would open the power valve and release the extra power. When you get to 10k and change to the next gear, although the revs drop you are still over 7k so you can leave the power valve lever where it is, and just keep going through the rest of the gears at full speed and on full power. Then when you slow down you can close it again and start all over again. Now this wouldn't be the best or easiest thing to use but it would give you full power when needed or a nice easy bike to ride around town. Now as I said earlier, I never got around to this because when I was younger I couldn't be bothered and I loved the power band I got from having the power valve full open. But anyway, I thought I would share my thoughts. Vince PS I have done 170 miles on my DT125R now, and I'm starting to open it up, and yes it does fly. I'll keep you posted how it goes when I let it have full throttle. PPS sorry for the long reply, when i get started I just cant stop .. lol Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 8, 2011 Moderator Share Posted June 8, 2011 instead of a hard to find mower lever you could use a mountain bike thumb front derailleur changer...much easier to find? but like you said it depends on having a spring strong enough to return the valve. Link to comment Share on other sites More sharing options...
BEng Posted June 8, 2011 Share Posted June 8, 2011 instead of a hard to find mower lever you could use a mountain bike thumb front derailleur changer...much easier to find? but like you said it depends on having a spring strong enough to return the valve. Sorry showing my age now, didn't think of using something as new as a "mountain bike thumb front derailleur changer" Link to comment Share on other sites More sharing options...
NEV Posted June 8, 2011 Author Share Posted June 8, 2011 Sorry showing my age now, didn't think of using something as new as a "mountain bike thumb front derailleur changer" Recently put a new manual choke lever/cable on the Motorhispania, just the job methinks, sits right alongside the switch gear. probably see a bit better on this pic Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 9, 2011 Moderator Share Posted June 9, 2011 god, far too bloody complicated. All these fancy lever idea's are fine but you have to use them. 2 choke cables the friction type, One with a H (high rpm) and one with a L (obvious) then you just pull the one that counts. That gives you infinate scope for an all round 'middle' and the extreems when you want to be silly. Believe me i'm going from experience here the more complicated the more hassle, springs are never the right tension. Link to comment Share on other sites More sharing options...
NEV Posted June 9, 2011 Author Share Posted June 9, 2011 god, far too bloody complicated. All these fancy lever idea's are fine but you have to use them. 2 choke cables the friction type, One with a H (high rpm) and one with a L (obvious) then you just pull the one that counts. That gives you infinate scope for an all round 'middle' and the extreems when you want to be silly. Believe me i'm going from experience here the more complicated the more hassle, springs are never the right tension. Cheers BEng, OG, & Cynic for your ideas, I'm going to have a looky round for the PV pulley and casing, and cables, and once I've got them on the engine in situ, I think I'll have a better idea of what I'll need to do, also I have a few different oil pump mechanisms I can cannibalise, but will have to check out fixing holes. For the main cable, the 'friction' lever type choke cable next to the switch gear on handlebars looks about the better idea so far. Anyroad I reckon this thread will be back in a couple of weeks, once I have parts and can see whats what Link to comment Share on other sites More sharing options...
rob_aka_chippy Posted September 29, 2011 Share Posted September 29, 2011 sorry to but in your conversation but does any one know where to get a lighitn coil fro c reg dt125lc2 because i cant find one anywhere on the net and yam main dealer wants bout 400 pounds,,,,,,if not a lightin coil what about a whole generator aany suggestions would be much appreciated because at the moment im stuck for ideas,,, once again sorry for butting in please help :shakeno: Link to comment Share on other sites More sharing options...
NEV Posted September 29, 2011 Author Share Posted September 29, 2011 sorry to but in your conversation but does any one know where to get a lighitn coil fro c reg dt125lc2 because i cant find one anywhere on the net and yam main dealer wants bout 400 pounds,,,,,,if not a lightin coil what about a whole generator aany suggestions would be much appreciated because at the moment im stuck for ideas,,, once again sorry for butting in please help :shakeno: You can go two ways with this Rob, buy a second hand stator with 2 coils on it (presuming its the 2 and not the 3 coil type) Ebay would be the road I'd go down or ring round your local bike salvagers, roughly takes about couple of hours,(tank&seat off, magneto casing off, and you'll need a flywheel puller mind, again Ebay) start to finish, taking old one off, then banging replacement in, , or you can buy a new one from someone who specialises in pattern stuff, and soldering it in yourself, would take an afternoon, ball park estimate, try Yambits, Yuniparts, CMSNL,Fosters, Damerells, see what sort of prices they quote. I had same problem couple of weeks ago myself, but replaced my stator with a second hand one. Just had a look at the CMSNL website they do a new replacement lighting coil assembly at 75 Euros (2coil type) gives an idea of price, and a damn site cheaper than £400. http://www.cmsnl.com...slist/A-08.html Right then I've just spent 10 minutes replying to this, now you need to go into your first post in new members and edit, and do a proper intro, it'll take about, 5 mins max. as it's normally something we require new members to do, forum ettiquette and all that. Cheers Nev Link to comment Share on other sites More sharing options...
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