Topic: custom wiring harness question using M unit blue

[algophobe]

i'm trying to go over my custom wiring for a cb750 k2 set up with m unit blue. possibly having some issue with adequate recharging of the battery. in comparison to numerous other wiring diagrams, does it matter if the 15A fuse is between the return (charging wire) from the rectifier to the battery? or should it hook directly to the battery?

second questions is if there needs to be any mods to the charging system if you switch to lithium battery? i'm using an 8 cell antigravity.

[calj737]

No, and no.

The only involvement the M-Unit has with the charging system is to use the RR BLACK wire connected to LOCK or AUX for battery reference.

[algophobe]

some one mentioned using Ricks special rectifier/reg specific for Li ion batteries. does that even makes a difference? I guess according to their website, its specifically set for Ballistics Li batteries.

[shads]

I thought that a R/R that is compatible with Li ion batteries is needed to prevent too high a voltage when charging.

[calj737]

some one mentioned using Ricks special rectifier/reg specific for Li ion batteries. does that even makes a difference? I guess according to their website, its specifically set for Ballistics Li batteries.

Yes, it can. They have a new 14-100 model (iirc) specifically for Lithium batteries.

I thought that a R/R that is compatible with Li ion batteries is needed to prevent too high a voltage when charging.

True, and, Lithium batteries have a different charge curve that the standard RR doesn’t map perfectly well to. New battery technology, new compatible charging technology. 

[algophobe]

some one mentioned using Ricks special rectifier/reg specific for Li ion batteries. does that even makes a difference? I guess according to their website, its specifically set for Ballistics Li batteries.

Yes, it can. They have a new 14-100 model (iirc) specifically for Lithium batteries.

I thought that a R/R that is compatible with Li ion batteries is needed to prevent too high a voltage when charging.

True, and, Lithium batteries have a different charge curve that the standard RR doesn’t map perfectly well to. New battery technology, new compatible charging technology. 

So could be the cause of premature battery failure like in my case with a regular RR

[calj737]

Possible. Not likely though. I’d suspect a bad ground from RR or a poor reference on BLACK to battery POS.

Once you get a fresh battery, runs some voltage tests:
Electrics off, voltage at battery
Engine at idle, voltage at battery, AND voltage on LOCK
Voltage between RR BLACK and battery POS (measures difference in battery reference)
Voltage at battery and LOCK with motor at 4,000 RPMs.

[algophobe]

Possible. Not likely though. I’d suspect a bad ground from RR or a poor reference on BLACK to battery POS.

Once you get a fresh battery, runs some voltage tests:
Electrics off, voltage at battery
Engine at idle, voltage at battery, AND voltage on LOCK
Voltage between RR BLACK and battery POS (measures difference in battery reference)
Voltage at battery and LOCK with motor at 4,000 RPMs.

Quick question, when checking the voltages in this location the black on the volt meter would be on ground? And the red on the meter would be at these various locations?

[calj737]

Yes, except for the test between RR BLACK and battery POS. (Bike not running)