Speedo

[Tuffers]

Hi all

I currently have an Acewell 3100 computer fitted to my 02 XR650R. After giving the bike a tidy up over the last few months I can't work out the wiring at all and no I didn't note the connections before I took it off!(Hindsights a wonderful thing!!). One of the previous owners used what I've now found out to be a bridging rectifier and a diode in the circuit I think but my electrical knowledge is poor. There is also a 12 volt battery in the circuit too.

Can anyone give me any guidance on how it should be wired. I've got the acewell wiring diagram but its no help as the rectifier, diode and battery aren't in the circuit. Otherwise I see I've got two options:

- Take it to someone who knows what they're doing and pays the money which would be frustrating because I've done the rest of the bike myself and I hate to admit defeat.
- Scrap the acewell and put on an original speedo etc which is appaeling from an originality perspective but the computer looks good.

Any help would be massively appreciated

Matt

[416cc]

Charging System Basics

Basically the XR650R dosn't come with a battery, & your speedo requires a system to power it. But it needs a stabilised +12v supply, rather than a 12v system feeding directly to the speedo which is only there when the engine is running. At least with a battery system you can use this for a DC horn, brake lights, possibly an electric starter, a feed for a sat nav...etc.

The link shows a car system, but a bike isn't disimilar. Your rectifier will take AC or alternating current, & make it into a +ve (or a -ve if that's what you needed) voltage of sufficient magnitude so's to be able to charge your battery & to give enough for ancillary components as already stated. The diode that you have is probably a zener diode which is used as a voltage regulator. If it's the right voltage type, this will 'spill off' or avalanche anything over what was required ie. 14v. You may well then need a seperate voltage regulator for a sat nav or a speedo which specifically requires 12vdc.

[Tuffers]

Thanks for the comprehensive reply - Think its a bit clearer now -Didn't think for one minute that it would be as complex as that or that the system would charge the battery.

Still not sure how to wire the bridge rectifier though - Having a fiddle with it last night and must have got the wires on the wrong connections of the bridge rectifier because the diode smoked and then broke in half!!

Whats that saying about 'if it ain't broke!!'

Will do a bit more internet research on the bridge rectifier and try and understand which wire goes on which spade. I have 2 wires coming out of the main bike loom which were connected and then two others from the speedo/battery - and then i'll head to Maplins for a new diode or 3.

Matt

[416cc]

Diode bridge - Wikipedia, the free encyclopedia

As you will see, the voltage coming out of the alternator of the Honda would be connected to the two AC inputs. The +ve of the rectifier side to the battery +ve. The -ve side of the rectifier would go to the nearest chassis point or common ground as it's otherwise known. The zener diode would go between the rectifier & the battery +ve, the idea being that anything over a specified voltage like +12.5v would be bled off...like an overflow tank on a loo.

The people who are really good with bike electrics are to be found at
Honda MX

[Mudwiz]

Have you a battery fittedd to the XR?
I've toyed with doing something similar on my Dad's bike, but the whoe thing runs original AC battery-less system?? I can't work out the help yet!

????

[jasonbc]

Thanks for the comprehensive reply - Think its a bit clearer now -Didn't think for one minute that it would be as complex as that or that the system would charge the battery.

Still not sure how to wire the bridge rectifier though - Having a fiddle with it last night and must have got the wires on the wrong connections of the bridge rectifier because the diode smoked and then broke in half!!

Whats that saying about 'if it ain't broke!!'

Will do a bit more internet research on the bridge rectifier and try and understand which wire goes on which spade. I have 2 wires coming out of the main bike loom which were connected and then two others from the speedo/battery - and then i'll head to Maplins for a new diode or 3.

Matt

You can bin the battery etc. When i fitted my trail tech (which will work on DC and AC) i used the background illumination cable from the original dashboard for the power source so as long as you ride with the lights switched on the acewell should be powered. I'm surprised the acewell hasn't got a battery back up my trailtech and hebo both have them

[Tuffers]

In reply to Mudwiz - From what I understand the bridge rectifier is the crucial bit for the installation of a battery because it converts AC to DC current. The addition of a zener diode between the +ve and the battery then allows any surplus voltage to spill over and charge the battery.

In all honesty, and in part response to jasonbc, the only thing the battery does is keep the clock running on the Acewell, otherwise it powers off of the engine. It seems alot of effort just to retain the clock memory and I've no intention of adding any further DC powered accessories so think I'll ditch the battery - So long as the Acewell will run on AC.

[jasonbc]

In reply to Mudwiz - From what I understand the bridge rectifier is the crucial bit for the installation of a battery because it converts AC to DC current. The addition of a zener diode between the +ve and the battery then allows any surplus voltage to spill over and charge the battery.

In all honesty, and in part response to jasonbc, the only thing the battery does is keep the clock running on the Acewell, otherwise it powers off of the engine. It seems alot of effort just to retain the clock memory and I've no intention of adding any further DC powered accessories so think I'll ditch the battery - So long as the Acewell will run on AC.

Even if it won't run on ac you can still pick up dc from the bikes wiring loom