Hi Chaps,
I've been lurking for a while, tried to join several times, but finally now have admin approval.
I bought and fitted a HPI 210 system to my RD400, as supplied by treatland, but the spark is so weak, it won't run. I've tried many things and nothing is working, including resistor / non-resistor plugs and three different coils.
I've added earths from the stator to the engine, engine to frame, engine to Coil, Coil to CDI. Black wire is connected directly to the coil ground, orange to the coil positive. The exciter coil has a resistance around 400 Ohm.
I can see with a timing light that it does fire at 2mm BTDC, but it's so weak I have to spin it over fast with a drill to get the light to trigger at all.
I've tried three different coils, no improvement. Unfortunately the coil supplied by treatland was single output, so I can't try that one, other than to say that the spark is stronger with one plug, wasted spark than two :/ Anyone know the primary / secondary resistance on the two output HPI coil ?
What else should I try?
First post so be gentle :)
Cheers.
AJ,
they should have supplied a 2 lead coil. which one are you using? I run an hpi on my 350, its def got good spark.
I would get a correct 2 lead coil from them.
also, disconnect your kill switch temporarily. see if its better. Ive chased an arcing kill switch on a cdi before, was hard to find.
Thanks. Treatland are sending a two wire coil.
Black / white kill wire is disconnected.
Edit: I've tried a banshee coil, RD350F2 coil and another performance coil. All work well in other bikes.
Mine had trouble sparking when I mounted the control box right next to the spark plug coil.
Quote from: 1976RD400C on July 10, 2022, 10:06:11 AM
Mine had trouble sparking when I mounted the control box right next to the spark plug coil.
Thanks, I'll try moving around a bit. Also got someone sending a load of HPI kit he's been testing, to me. Hopefully we can eliminate what the problem is.
Still curious what the primary and secondary resistance of the supplied coil should be, if anyone can check?
Appreciate the helpful responses, Cheers.
Quote from: ajb on July 11, 2022, 03:57:52 AM
Quote from: 1976RD400C on July 10, 2022, 10:06:11 AM
Mine had trouble sparking when I mounted the control box right next to the spark plug coil.
Thanks, I'll try moving around a bit. Also got someone sending a load of HPI kit he's been testing, to me. Hopefully we can eliminate what the problem is.
Still curious what the primary and secondary resistance of the supplied coil should be, if anyone can check?
Appreciate the helpful responses, Cheers.
The twin spark plug coil that came with my HPI is:
Primary, spade terminal on coil to ground .7 ohms
Secondary, meter connected between the 2 spark plug caps (not resistor caps) 7660 ohms
make sure you didnt pinch a wire behind the stator plate as well.
Thanks chaps.
More checking to do when I get back in the garage.
I finally received the two output HPI coil and tested the capacitance, in spec according to 1976RD400C's very helpful reply.
Still no joy spark is too weak to start it. Even to check the timing, the drill has to be running near flat out. Weak spark is at 2mm BTDC, nothing has slipped.
Wires not pinched on the stator plate and do have continuity to the CDI box. CDI box moved away from the bike, no difference in spark. Not running resistor boots or plugs. So I'm running out of ideas.
One thing, I didn't lap the rotor, so the flywheel is sitting approx 3.5mm or 9/64" from the stator plate. Is that normal?
Got a friend who has a load of HPI kit, sending it to me for testing. Hopefully I can get to the bottom of this.
Thanks for your help, Cheers.
yeah, thats very strange indeed. ive never had an issue with one sparking.
Could be charging windings are bad behind the rotor. Or something metallic stuck to it under the rotor.
Yep, I'm baffled.
The exciter coil has a resistance around 400 Ohm, so I think that's ok. I don't think the charging / lighting windings are being used here. I have no relay fitted.
Hopefully I'll have some kit to try soon and narrow it down. Does the flywheel clearance at 3.5mm or 9/64" from the stator plate sound about right?
I'm thinking that perhaps the flywheel magents are slightly proud of a small part of the coil.
this is how mine sits on my bike (rd)
(https://www.2strokeworld.net/wp-content/uploads/lightweight-rd/hpi-cdi/project-ign2-pegs_03_zps5eelgf5e.jpg)
you def cant see any of the coils. .02
on the cr85 motor:
(https://www.2strokeworld.net/wp-content/uploads/G3SS/motor-rebuild-etc-22/cdi-and-electrics/g3-cr-cdi-electrical-22_9-rotated-e1659554811689.jpg)
Thanks, that looks quite similar.
That's odd. I'm doing a teardown on my 400 and just removed the HPI. This is how my coil plate is positioned.
(https://i.ibb.co/MZCPgvp/hpi.jpg) (https://ibb.co/2WkcF9P)
it can be clocked however you want it tbh. since the rotor doesnt have a keyway and all... .02
I should get some HPI parts to test by the weekend, will update this thread when I've had a chance to give them a whirl.
Thanks.
Hope you work it out. If you were closer I would suggest you bring all the parts over and we could run them on the ignition test jig and see what's going on.
It's not sophisticated but enables us to test timing, spark strength, revs it starts to fire at, revs it breaks up at but I don't run it over 12,000 revs because I hate to have metal parts shooting across the shop if/when thing break.
Quote from: teazer on August 04, 2022, 03:33:09 PM
Hope you work it out. If you were closer I would suggest you bring all the parts over and we could run them on the ignition test jig and see what's going on.
It's not sophisticated but enables us to test timing, spark strength, revs it starts to fire at, revs it breaks up at but I don't run it over 12,000 revs because I hate to have metal parts shooting across the shop if/when thing break.
Thanks. Let's see how it goes, fingers crossed!
Just to wrap this one up, got the 400 finally started up on the HPI system. Now to take it for a spin.
A float was stuck on on carb, also the coil connection was slightly loose. Happy days.