Topic: Speedo drive for 18 inch front wheel on cb550

[Turbogrimace]

I put an 18 up front on my cb550, which would throw off the speedometer. I installed a cb400f speedo drive some they came with an 18 from with a 15 mm axle. Unfortunately my speedo is reading high.

Its 5 over at 30 and 10 over at 60. Anyone know how to correct the speedo?

[Bankerdanny]

You need the 400 speedometer too. It isn't just a question of the drive at the wheel, the ratio at the gauge is different too.

[Turbogrimace]

The ratio in both gauges is 2240

[CycleRanger]

Yep, the speedo ratios are the same for all the fours.
If your gauge has leaked any oil it can cause it read high. (There's a thread here somewhere about refilling gauges)
Does it have a stain on the face? That's a sure sign.

Otherwise, these gauges weren't that accurate even when new, especially when compared to GPS.
Off on the high end doesn't surprise me that much but at the low end 5 over at 30 seems a bit much.
The speedo on my K5 is ~10 high at ~60. (Says 70 when going 60.)
I think that's how they sold more bikes.

[Turbogrimace]

No stain, pretty clean. I'd like to find a new gauges set anyhow, but I heard the 400 f drive wold solve the issue. I might swap my 550 drive back in just to see what it reads.

[CycleRanger]

No stain, pretty clean. I'd like to find a new gauges set anyhow, but I heard the 400 f drive wold solve the issue. I might swap my 550 drive back in just to see what it reads.

Where did you get the 400F drive? maybe it's not a 400F drive?

[Turbogrimace]

I considered that too. It had the same tooth setup as a 400 drive but that was only based on pictures I found.