Speedometer and Tachometer ratios - once and for all

Ok, I've search the forums, googled a lot and spent a number of hours on this, and I'm still not clear over the ratios for the speedos and tachos on our bikes. I find inconsistent information all the time, and would like a clarification from someone who actually knows (and not guessing).

TACHO
Some people have said that 5:1 ratio is suitable for Kawasaki and Yamaha, while 4:1 ratio is suitable For Suzuki & Honda. But I've also seen ads (mostly on eBay) for 4:1 tachos "for Honda, Yamaha & Suzuki", as well as 7:1 tachos for Honda and even 4:1 tachos specifically for Yamaha.
Perhaps it's not as simple as "this brand has this ratio, that brand has that ratio", but it can differ from model to model (or at least series to series)?
The most important thing for now: Can anyone confirm that the Yamaha XJ bikes (specifically XJ550 4V8) uses a 5:1 ratio tachometer?

SPEEDO
I've seen people stating that there is no difference in speedometers, they are the same except for mph vs km/h. (where 2240:60 for mph and 2330:100 for km/h). Yet some vendors state a ratio of for example 1:1, 2:1 on their products. What should I look for? In my case I want km/h since that's what we use in Sweden (and most of the world). Do I ONLY have to look for km/h, and that it's driven by a mechanical cable, or should I be aware of anything else? Are there several types of mechanical speedo cables, or is it all standardized?

 

Tach: I think 5:1 is correct but I can't confirm it.

Speedo: The 2240:60 mph or 2330:100 kph is pretty universal across all of the makes (and Yamaha models) of the era.

There are different styles and sizes of things like the input stub where the cable screws on, but as for Yamaha stuff they're pretty much all the same. I have a 150mph speedo from an XJ900 in my XJ550RK (4U8) and it pretty much dropped right in.

 

Thanks bigfitz, that is the most common answer I've found.

Just to explain the background to my questions:
I'm planning to rebuild my bike and want to replace the instrument cluster with a brand new (smaller) speedo and tacho. So I'm not looking at replacing it with other 30 year old gauges and therefore want to know what I should be looking for that's new on the market now.

I hope I'm not coming across as rude, if so I apologize. I'm just confused by the inconsistent information out there, and only want to make sure that whatever I buy will actually fit, since my budget is less than optimal.

 

No worries; I understand completely and I didn't think you were coming across as rude.

MikesXS, here in the States carries a wide selection of smaller than original, neat and best yet, compatible gauges. Although they cater specifically to the XS market, due to Yamaha's inherent standardization stuff that works on '80s XSs also works on '80s XJs.

The problem I had was that my 4U8 550R came with an 85mph speedo.

That just won't do. The only drawback to this transplant was that I lost the trip odo reset. It was worth it. I have a matching electronic tach to install in it when I get around to it; for now the original tach with a repainted needle will do.

 

Thanks for the tip!

What seems to be common for the mechanical variants at MikesXS is:

For speedometer
Calibrated for 19" front wheel. 2:1 ratio.

For Tachometer
Mechanical (cable drive) type. 1:5 ratio.

I guess I have my answer there.

I have one concern though. I recall reading in on or two threads here that both the speedos from MikesXS are "horribly off" (I'm pretty sure that was the term used), reading way to high. But perhaps that was a special case and not caused by wrong ratio?

 

fitz - why did you lose the ability to reset the trip odometer?

 

the trip odo reset on the 150mph speedo was by a "push button" mechanism that placed the button between the speedo and tach. It had to be removed.

What it did was to "convert" the pushing of its button to rotational motion and rotate the shaft in the center of the odo just like the knob does on the other units. Once I get ambitious enough I'll figure out a way to reattach a conventional reset knob; which will require somehow extending the shaft out the LH side of the instrument.

You can see the "offending" mechanism in this pic. Luckily, it simply unscrews from the instrument frame.

Another item of note in this pic is the different angle of the input "stub" on the pictured instruments. From left to right we have:
-the stock speedo; -the 150mph unit; -guts from a "canned" instument.

You'll see that the "cluster" instruments have their input stubs at a different angle than the one from a "canned" unit.

 

What machine are these instruments from and will they fit the XJ 900f
.

 

They would look great on the 900 SpearChucker. The ones Yamaha put on the bike are okay but I prefer the ones in the picture.

 

Mine have had a few scrapes and look rough. I might trade them up if I can find a decent set

 

The case on mine were cracked and l got a set on EBay so they look good. I would like them to be brighter but l don't know if it is possible to do that.

 

You can but LED bulbs for them. I put new bulbs in mine a couple of months back but it’s still pretty dim. I have a new LED for the headlight due here next week and I think I’ll look into LEDs for the console too. I may not get to try any of it out as it is currently snowing!

 

Do you need a relay with LED bulbs, I am not sure but if you fit them in the instruments can you let me know if they are brighter thanks.

 

Here's what my LED instrument cluster lighting looks like. definitely not dim.

 

Yes I like your LED lights I am going to try them in my bike thanks.

 

How did you go in your quest to find some smaller gauges?
I am looking at the same thing.