A forum for owners of Yamaha TTR250 trail and enduro bikes!

Christos · Veteran Member

Replacement Speedo for digital Speedo version

TTRfan · Super Guru

Hi Christos

Information on the wiring here

Brian

Christos · Veteran Member

Thanks a lot Brian!

Christos · Veteran Member

Need some further help guys...when the magnet is at the front sprocket, what can I program to the Speedo as circumference? Is the OEM Speedo the only compatible with this setup?

-- Edited by Christos on Wednesday 9th of June 2021 07:07:57 PM

mossproof · Super Guru

This is where it gets complicated!
I am assuming you have a speedo that works off a magnet pulse on the front wheel?
Measure the distance the bike travels for one turn of the front sprocket. That will give you an equivalent value to the front wheel circumference. BUT, I believe the sprocket mounted magnet will give you 2 pulses per rotation, so you need to halve the distance for 1 pulse. I think.
You might not be able to use the sprocket magnet if the circumference input range does not go low (or high) enough. If the speedo works with multiple magnets, you might be able to tune the figures to make it work!
Good luck!!

Christos · Veteran Member

Really valuable information! Thank you for sharing!

Christos · Veteran Member

Hi guys,

I sorted out the Speedo main wirings but I am confused about the indicators: left, right, high beam, neutral. The new Speedo has one cable for each indicator and has to be connected to the positive side.

Does anyone have a wiring diagram for the OEM connections? Any advice is welcome.

Christos · Veteran Member

Anyone that knows about the connector's 6 cables?

mossproof · Super Guru

Does this help?

ttr250.activeboard.com/t62758425/wiring-diagram-for-white-93-open-enduro/

If you want left and right indicator warnings, the simplest is to bring a wire from each indicator up to the new speedo.

Christos · Veteran Member

mossproof wrote:
Does this help?

ttr250.activeboard.com/t62758425/wiring-diagram-for-white-93-open-enduro/

If you want left and right indicator warnings, the simplest is to bring a wire from each indicator up to the new speedo.

Hello Simon,

it helps a bit!

For instance, the new speedo has one cable for neutral (has to be connected to positive according to instructions). Is it the light blue positive or the brown one? for the high beam is the yellow or the black positive? because the speedo has one wire per indicator i tried to test each one but the lights remained on even with the high beam switch off for example. Your expertise kindly needed once more!

mossproof · Super Guru

For the high beam warning light, power comes to it down the yellow wire. Black goes to earth/negative.

I will have to dig out a wiring diagram for the other two...

When you tested the indicator warning lights, was there a "load" bulb wired in? The relay won't flash unless it has the indicators connected (unless you have leds and the correct relay for led indicators)

What make is the Aliexpress speedo? Pics of the wires/wiring instructions? (Or are they in Chinese?)

-- Edited by mossproof on Thursday 9th of September 2021 08:40:04 PM

ttr steve · Super Guru

Any good

electrical 2.png

Christos · Veteran Member

It says MLS052 Simon. I have the OEM indicators and relay, no load I believe. I will give it another try tomorrow. Here is the first page of the instructions. Only connections to positive side for the warning lights, no negative connections or even cables.

Thank you Steve for the diagrams!

mossproof · Super Guru

Thanks Steve!

Indicator warning light (3 wire relay): My interpretation of how it works: Brown wire is positive feed. Brown and yellow puts in positive 12v from the relay when it is NOT flashing. This means net voltage is zero. When the relay closes to flash the lights, it opens the wng lamp circuit and the 12v from the brown wire goes down to earth, so illuminating the bulb. This is also how a car alternator/charge warning light works. Don't worry if you don't get it. What it means is IGNORE THE ORIGINAL IND WNG WIRES and just bring separate wires up from the front indicator lamps to the new speedo. The new speedo presumably has a common earth for most of it's functions.

mossproof · Super Guru

OK

Bring a wire up from the positive wire connector of your left hand indicator to the orange wire in the speedo connector block (9)
From the right hand indicator to the light blue (3)
The yellow wire coming from the main beam headlight switch goes to blue wire (6) in the connector block

All these warning lights earth out through the green wire (Honda like to use green for negative!) number 4 in the block.

I don't see a neutral warning light mentioned??

mossproof · Super Guru

Found some instructions online.
Next page in your manual says green/red for neutral light? (On another connector block for the gear position sensor?)

I think you will have to get your multimeter out for this - the neutral light on a ttr is controlled by "complex" wiring coming from the cdi. It's probably actually quite simple, but my brain won't calculate it at the moment, so test what comes out of the original neutral light wires (from each wire to earth, and between the 2 wires, when the bike is in gear, and in neutral. You are looking for +12v when the bike is in neutral, and this, I THINK is the wire to connect to the speedo IF they suggest it needs a positive - I believe this also earths through the green wire.

Because the neutral light is part of the starter inhibitor circuit, the starter might not work. I'm not sure.

If you can wait a bit longer, I will have a look at my 350's Koso speedo to see how I wired that. Not tonight!

If someone else out there can double check my theory here I would be grateful!!

Christos · Veteran Member

Thank you Simon! I really appreciate your help. Will have a try tomorrow.

mossproof · Super Guru

The Koso speedo I have on my 350 uses the blue wire from the neutral light loom. Hopefully this will work for you. I think the brown wire is a positive feed, so will leave the light on permanently.
Good luck!

JOHNYBOY · Super Guru

i fitted a trailtec good value for money £79

Christos · Veteran Member

mossproof wrote:
The Koso speedo I have on my 350 uses the blue wire from the neutral light loom. Hopefully this will work for you. I think the brown wire is a positive feed, so will leave the light on permanently.
Good luck!

Yes Simon. That is why the light was on all the time with the brown wire. I made a special aluminium holder yesterday and today will proceed with fitment and calibration. I will post some photos afterwards.

Christos · Veteran Member

JOHNYBOY wrote:
i fitted a trailtec good value for money £79

Trailtech uses two sensor wires, I needed three to use the OEM sprocket sensor so I searched for an alternative.

Christos · Veteran Member

Ongoing...

-- Edited by Christos on Saturday 11th of September 2021 02:32:53 PM

Christos · Veteran Member

Well, for the blinkers... I joined left and right Speedo cables as I did not mind both flashing. Bad luck, in the first loom position they flashed all the time and in the second they were constantly on.

Simon, I think the way you suggested directly to the front blinkers' positive cables is the only simple solution. Thank you for the good will and help!

-- Edited by Christos on Saturday 11th of September 2021 07:49:00 PM

JOHNYBOY · Super Guru

trailtek uses a magnet on the front wheel take one bolt that holds the disc on & replace it with the bolt supplied with the magnet on it

Christos · Veteran Member

JOHNYBOY wrote:
trailtek uses a magnet on the front wheel take one bolt that holds the disc on & replace it with the bolt supplied with the magnet on it

Yes, you are right. I just wanted as much OEM setup as possible. Trailtech is a well-trusted company.