Hi Guys,
Well, 2024 is turning out to be a bitch of a year so far. Been scammed twice at over £200 a pop, various motorcycle related disappointments and now something MUCH more worrying.
OK, well, I own an XS650 street scrambler, with 750 big bore, 270 rephased motor, running a Probe Engineering electronic ignition. The 270 motor was built by the now deceased Daryl Hutcheon, in Australia, and has done a total of approx. 2500 miles since being rebuilt/rephased. Performance was below par, and on inspection it turned out that the cam had been ground wrong (way too much overlap). Consequently I had to have a new cam ground here in the UK. Its all back together again and today I stuck it on my friends rolling road and tried to get it to fire up. After many failed attempts, a re-check of the ignition timing with the light gun showed the timing had been set to the wrong crank rotor TDC mark. This was put right and hey presto the bike fired up instantly. After giving it a good warm up and adjusting the tickover the motor seemed to be close to achieving a reasonably tickover but didn't quite feel right, like too much vibration at the bars. Fired it up again, double checked the ignition timing and it appears that the Probe system wasn't advancing the ignition as it should. I was running it at about 4000 rpm when suddenly the motor instantly revved to 6000rpm (so quickly the motor torque forced the rear suspension down sharply). It sounded and ran, for those few seconds, absolutely AWESOME! Truly amazing feel. Anyway I reduced the throttle back to 4000rpm upon which the motor ran a little eratically then just simply cut. Fired it up again, ran it up to 4000rpm (felt eratic like it was on one cylinder) and then it simply cut again. At this point it failed to fire up again after several attempts. So, I decided to re-check the static timing.
With the Probe there's a red LED light on the control unit that goes goes bright red during the dwell period then goes dark at the 'firing event', i.e at 36 degrees (fully advanced)BTDC. This is how the Probe system works and has to be set up. However, NOW the red light won't light up at all, when the crank is rotated with a wrench. Just nothing. When you turn the ignition on and off, and when you flick the kill switch off and on, there is an instantaneous faint, momentary red glow from the LED, but no constant bright light when there should be. The ONLY way I can get the LED to display bright red is when I unplug the 8 pin timing sensor connector from the control unit. Plug it back in and the LED light goes out.
My BIG BIG fear is that either the control unit or the timing sensor has failed. There are no 'trouble shooting' instructions in the Instruction Manual, so no way of testing if its failed or not. This is a huge problem because Probe Engineering no longer exist and I know of no other supplier for a true 270 ignition system for the XS. I've tried calling and emailing Michael Whitebrook (Probe Engineering) but this has been fruitless. As the designer and builder of the electronic ignition system is no longer contactable and the motor builder is deceased, I'm beginning to think I may be 'up the creek without a paddle'. Whilst I appreciate sh*t happens, I'm finding hard to accept that a piece of equipment of such engineering quality as the Probe system, would fail only 2500 miles from new.
So, my question is: does ANYONE have ANY idea if there is still a source ANYWHERE for a 270 Probe set up that I could acquire (control unit and sensor) or does anyone know of a 270 degree system that is available for the XS, be it cam driven or crank driven? The motor currently has a Sparx PMA fitted. If my existing ignition system has failed and if I can't source another system to suit a 270 XS, then I end up with a bike that is little more than a VERY expensive ornament.
ANY INFORMATION TO HELP ME CONTACT THE PROBE GUY, OR POINT ME TO ANOTHER VIABLE OPTION WILL BE VERY MUCH APPRECIATED.
Well, 2024 is turning out to be a bitch of a year so far. Been scammed twice at over £200 a pop, various motorcycle related disappointments and now something MUCH more worrying.
OK, well, I own an XS650 street scrambler, with 750 big bore, 270 rephased motor, running a Probe Engineering electronic ignition. The 270 motor was built by the now deceased Daryl Hutcheon, in Australia, and has done a total of approx. 2500 miles since being rebuilt/rephased. Performance was below par, and on inspection it turned out that the cam had been ground wrong (way too much overlap). Consequently I had to have a new cam ground here in the UK. Its all back together again and today I stuck it on my friends rolling road and tried to get it to fire up. After many failed attempts, a re-check of the ignition timing with the light gun showed the timing had been set to the wrong crank rotor TDC mark. This was put right and hey presto the bike fired up instantly. After giving it a good warm up and adjusting the tickover the motor seemed to be close to achieving a reasonably tickover but didn't quite feel right, like too much vibration at the bars. Fired it up again, double checked the ignition timing and it appears that the Probe system wasn't advancing the ignition as it should. I was running it at about 4000 rpm when suddenly the motor instantly revved to 6000rpm (so quickly the motor torque forced the rear suspension down sharply). It sounded and ran, for those few seconds, absolutely AWESOME! Truly amazing feel. Anyway I reduced the throttle back to 4000rpm upon which the motor ran a little eratically then just simply cut. Fired it up again, ran it up to 4000rpm (felt eratic like it was on one cylinder) and then it simply cut again. At this point it failed to fire up again after several attempts. So, I decided to re-check the static timing.
With the Probe there's a red LED light on the control unit that goes goes bright red during the dwell period then goes dark at the 'firing event', i.e at 36 degrees (fully advanced)BTDC. This is how the Probe system works and has to be set up. However, NOW the red light won't light up at all, when the crank is rotated with a wrench. Just nothing. When you turn the ignition on and off, and when you flick the kill switch off and on, there is an instantaneous faint, momentary red glow from the LED, but no constant bright light when there should be. The ONLY way I can get the LED to display bright red is when I unplug the 8 pin timing sensor connector from the control unit. Plug it back in and the LED light goes out.
My BIG BIG fear is that either the control unit or the timing sensor has failed. There are no 'trouble shooting' instructions in the Instruction Manual, so no way of testing if its failed or not. This is a huge problem because Probe Engineering no longer exist and I know of no other supplier for a true 270 ignition system for the XS. I've tried calling and emailing Michael Whitebrook (Probe Engineering) but this has been fruitless. As the designer and builder of the electronic ignition system is no longer contactable and the motor builder is deceased, I'm beginning to think I may be 'up the creek without a paddle'. Whilst I appreciate sh*t happens, I'm finding hard to accept that a piece of equipment of such engineering quality as the Probe system, would fail only 2500 miles from new.
So, my question is: does ANYONE have ANY idea if there is still a source ANYWHERE for a 270 Probe set up that I could acquire (control unit and sensor) or does anyone know of a 270 degree system that is available for the XS, be it cam driven or crank driven? The motor currently has a Sparx PMA fitted. If my existing ignition system has failed and if I can't source another system to suit a 270 XS, then I end up with a bike that is little more than a VERY expensive ornament.
ANY INFORMATION TO HELP ME CONTACT THE PROBE GUY, OR POINT ME TO ANOTHER VIABLE OPTION WILL BE VERY MUCH APPRECIATED.
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