Cb 750 F2 ( I know it not a grey bike)

[BigDonk]

I know its not a grey bike, my mate has one, but it just died the other day, as in no electrics, put in the key nothin, no dash lights, no start, absolutly dead, checked the usual culprits, battery fuses even the 30 amp fuse
in the starter relay, all are fine, a real head scratcher, would it be the ignition switch? as I cannot thinkit would be the rectifier or the cdi unit as I would have thought you still would have got the dash lights to come on, neutral,oil etc but we get abosulutely nothing

any clues anybody

[Superjack44]

1 First thing make sure there is life in the battery, check any and all connections for any sign of corrosion (usually greenish colour) and either repair or renew the connector.
2 Make sure all earth connectors are in a good clean sound condition if not repair or renew.
I have never seen one of these machines but assume they have multi block connectors in the wiring loom so as to connect to different components disconnect a multi block and inspect each one again for signs of corrosion and either clean or repair if neccesary.
4 Has it a kill switch fitted but this is unlikely to disable all power.
5 Regulater/rectifier problems can kill the battery and cause significant problems, if it is the reg/rec remember to replace both battery and reg/rec at the same time, reg/rec problems are a pain in the a**e and can be difficult to find .
There is a fault finding chart on this site somewhere that do a search and follow the advice it gives and you should come up with the solution to your problem.
Ps the power must come through the fuse board so check there first even remove and check underneath for breaks etc.

[BigDonk]

Hi SuperJack

the battery is almost new (3 months) and fully charged, couple of tests we did wire direct to starter motor that spun ok, swapped battery into my vfr started ok, full electrics, no problems, we cleaned the earth lead connections from the battery to the frame

the thing thats puzzling is that its totally dead, if the rectifier was away and not charging the battery, we should still get lights on the dash, neutral, oil,etc,when the battery is fully charged,fuses ok, we are getting not a glimmer, and are wondering if it is the ignition switch, unusual, but we will check the connections anyhow, did a search on the web found some guy with the same problem but on a nighthawk, this was on fixya.com, he basically said the same things, fuses,relay fuse, earth leads, battery and possible damage to the cdi/rectifier due to reverse polartiy (wihich I assume is the wrong battery being wired normally but wired up to the wrong terminals)

I do hate electrics especially when to some people it seems so simple

[Superjack44]

Hi SuperJack



I do hate electrics especially when to some people it seems so simple

We understand each other, I do too.
The way I would go about it is to check the wiring from the battery forward ie battery to fuse board/block make sure there is power there if not why not, then to ignition switch again make sure there is power there if not why not,then from there to where the power goes to various componets.
If there is no power going to a component then the problem probably lays between it and the battery just make sure the earths are good.
Thats about the limit of my electrickery knowledge even that could be wrong but good luck with it.
Jack