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CB1100 injector info.
hughpinder - 5/2/09 at 11:24 AM

I have just bought some CB1100 throttle bodies(42mm at butterfly), but can't find the resistance of the injector, or max flow rate. Does anyone know these? Can you just use a multimeter for the impedance? Can you just set up the fuel pump and give 12V to the injector for 1 minute to check the max flow?

Thanks for any help
Hugh


BenB - 5/2/09 at 11:38 AM

Impedence isn't the same as resistance but you can use the resistance setting of a multimeter to approximate it. If its around 2-3 ohms they're low impedence if it's 12-13 it's high impedence.

Wacking 12v across high impedence (peak+hold) injectors would be a bad thing. It may burn them out and wouldn't give you their max rating as they're not designed to work that way.

Putting 12v across low impedence injectors would be less of a problem though they might not like having 12v across them 100% of the time. I suspect ECUs max out at 99.9% (ie a very short off time). If you've got spare injectors give it a go if not wait to see what anyone else thinks


hughpinder - 5/2/09 at 11:44 AM

Thanks for that, I'll try them with a meter tonight, but wait and see if anyone can come up with a flow rate. Annoyingly I know the later version CB1100 blackbird used 335cc/min injectors(mine is a 99-2003 throttle bodies). Sorry forgot to mention the date and also the injectors are keihin ones with AAS B on one side, PA16 on the other - no info on the honda or keihin web sites though

Hugh


BenB - 5/2/09 at 11:52 AM

If they are low impedance you might get away with it if you flow fuel through them whilst you hold them wide open with the 12v (to keep them cool and prevent burning out the coil) but when I say fuel I mean white spirits. Don't use petrol else you'll spend a long time recovering in the burns unit....


MikeRJ - 5/2/09 at 03:34 PM

quote:
Originally posted by BenB
Wacking 12v across high impedence (peak+hold) injectors would be a bad thing. It may burn them out and wouldn't give you their max rating as they're not designed to work that way.

Putting 12v across low impedence injectors would be less of a problem


Other way around; low impedance injectors require current limiting built into the injector drivers (e.g. peak-hold), high impedance do not.