Bonneville America Forums Forums Technical Forums General Tech Speedo check

Maybe, just maybe I can get a sort of kind of better read on my speeedo…..
It’s a 2004, so its got the 790 motor, AI removed, stock pipes, 16 tooth sprocket, stock exhaust.
In 5th gear, at about 3000 rpm, the speedometer reads about 60 mph.
At 3500 in 5th gear it reads about 65 mph.
At 4000 in 5th gear it reads a little bit more than 70 mph.

Ok, these are approximates, so I can't say of it was uphill, downhill, with a crosswind, tailwind, but I can say that temperature was about 65, it was overcast and Elvis is still dead.

Soren

warranty issue. the speedo's toasted. no one else that i know of has had those readings. maybe the cable, too?

cat

thats about what mine reads with a 17 tooth

frank

I think when it comes to speedos the best thing people can do is have someone follow you in a car and clock you. I did it with my girlfriend. I would raise my hand at a given speed, like 60, 70, 80, etc. Then when we stopped I asked her what she was doing each time I raised my hand. So now I know what MY speedo is relative to traffic. Sounds like we're never gonna get a concensus on what the deal is with our speedos, so make sure you know YOUR speedo so you have an idea of how much to lie to the smokey that pulls you over:)

After several checks including roadside radar wagons (with the big "your current speed is..." sign) and comparison with other vehicles, it looks like mine tracks perfectly, but reads 10 MPH high.

same here.

Mine is a consistant 10% off at all speeds according to my GPS. I frickin' hate it.

Standing offer of $100 to anyone that can calibrate my OEM speedo to be spot on...

Same here. 10% by GPS. Sounds like they did it on purpose. My concept of a fix was to print a plastic overlay that looks like the speedos numbers but all the markings will be off by 10% compared to the original one. I bet it wouldnt be that hard to make. Any graphic artists?

I think ImOk has a great idea. I wonder how hard it wouyld be to dissassemble the speedo to get that sticker inside?
I might even put my speedo back on if it were accurate. Then again, maybe not. My new speedo has a clock in it. And its programmable. And its switchable from metric to imperial. And it remembers riding time and highest speed. And it only cost 20 bucks.
It's looking like the stocker will stay on the shelf in my garage.

'04 Speedmaster. 5th gear at 3000 rpm= 50 mph.

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'04 Speedmaster. 5th gear at 3000 rpm= 50 mph.

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I paid a little closer attention yesterday to my rpms and the traffic, that sounds about right. I also think that the 10% is about right too.

Just one more thought. Since the speedo runs off the front tire, I wonder how much air pressure affects the speedometer reading.

Soren

the sticker I dea is probably the best bet. Recalibrating is gonna be tough while not messing up the odometer!! You could even get into the housing and physically move the current plastic number plate over.

At 85 mph the tach reads 5000 rpm. I was riding last Saturday with a buddy who has a new Suzuki Boulevard 1600. At 50 mph and 80 our speedos read the same. I have yet to check it with a car. The radar wagons have showed 35, matching my speedo reading. A Metro officer showed 45 on his radar last year, again matching my speedo.(25 zone)

I doubt you could rotate the plate since the slot for the odometer will be out of whack and the Triumph name will be at an angle an not look good. But you could use whiteout paint and make small stickers with MPH numbers on them and stick them at the corresponding corrected MPH on the speedo. May not look bad.

Since its 10% error, the difference is obvious starting at 40MPH. You then would put a sticker over the 44MPH=40MPH, 55MPH=50MPH, 66MPH=60MPH, 77MPH=70MPH, 88MPH=80MPH, 99MPH =90MPH and so on.

just take it apart and scan it and use photoshop to change it. If someone wants to scan it for me I can change it and post it then you can just print it. then it will just lay overtop the otherone. get it laminated so that it will not warp. That way you dont even need to change the origional one

send me the big file at thejunki@hotmail.com

I just measured the back plate without removing it. The radius is 10cm. The actual printed circle is 9.5cm. If we can make an exact scan like you suggested, fix it and print it on self adhesive paper then we can flip the speedo plate and glue it to the backside without damaging the front. Why we can even make it where people can add their own custom graphic or background.

Staples sells self adhesive paper or some sort of real glossy paper.

Also since the speedo is exponentially incorrect the markings will be spaced exponentially between them. Can you do that?

Don't forget that whatever paper you use needs to be somewhat translucent so it lights up at night!!

If you can get your speedo apart, then you should be able to get to the flat coiled spring that is attached to the indicator needle. One end connects to the needle post and the other end connects to a (usually) movable piece.

Just move the movable end till you get the right speedo mph reading. The mileage indicator will not be affected, of course.

If your speedo comes apart, but you don't feel confident working with it, take it to a speedo shop. In the Phoenix area there are a couple, including the famous Dick's Speedo-Tach.