Seca 550: 150mph speedo retrofit details w/pics

Finally dug through the archive and found all the pics necessary to show you how I accomplished this:




The first step was tear apart the original cluster; that is covered here: http://xjbikes.com/Forums/viewtopic/t=14948.html


Next was locating a suitable "drop in" replacement speedo. I originally planned to use a 125mph unit freed from its can, but soon discovered that old "same but not" Yamaha syndrome.

Then by a stroke of luck, I located an NOS speedo from an XJ900 on eBay and the project was back on:



Stock speedo on left; then the new XJ900 unit; and the formerly canned instrument at far right.

Note the difference in overall depth/shape of frame, and angle of input bearing between the canned unit and the two to its left.

The big goofy trip odo reset on the new unit comes right off with two or three screws. Note however, the shape of the opening in the back of the internal cluster housing for the speedo.

That presented the next challenge: Note the support plate for the input bearing on the new unit (left) compared to the original (right.)




A little work with my Dremel and an Exacto knife yielded a modified housing:




Then the new unit fit right in; I improvised a couple of "retainers" from clipped and bent washers, providing a positive mechanical mount for the new speedo:




Then it was just a matter of painting all the needles to match:



Red on the left, orange on the right. Not a WHOLE lot of difference once dry; I ended up using the orange.

I also "tarted up" the tach to sort of match the speedo; I have an electronic tach that DOES match that I will install one of these days.

The only downside for the whole thing was the loss of the trip odo reset; but that is only temporary until I figure out how to "reverse-adapt" the old spinning-knob reset to the new instrument.

Meanwhile I simply plugged the hole in the housing with a black body trim fastener.

It sure is nice to know how fast I'm going.

 

What do the American market have as standard? 80mph?

Stock on this side of the world was 200kmh but no mph markings

 

Yep; '81-'83 were the 80mph abominations.

 

dude. where'd you get that clock? its freaking awesome.

 

Actually, it was 1980 through 1982 : three model years there. And the top was 85, not 80mph. Even Corvettes were thus crippled.

1983 models could once again know when they were above 'parking velolcity.'

 

Except for one minor detail: That IS a 1983 model year bike.

Simple fact of the matter is, most "1983" models were simply '82s in different trim. My '83 was built in MAY of '82. There were very few "true" 1983 models, especially for Yamaha. The industry was in a major slump at the time. So a lot of 83s ended up with goofy speedos too.

The clock is a Formotion (made for motorcycles) GA-72000 "stick-on" mount http://www.formotionproducts.com/BO%20Classic1.htm not cheap but not all that bad and worth it.

 

what size speedo (bike/year, diameter, anything really) will fit in a 550 maxim? ever since i've seen this i can't stop thinking about doing something similar to my bike. i've been trying to find a 120mph one on ebay but im not sure what to look for. i'm less concerned about having it match as well as yours but still want it to look similar at least. any ideas?

ive found some on ebay after searching a bit, would this work?
http://cgi.ebay.com/ebaymotors/ws/eBayI ... K:MEWAX:IT

 

Your best bet is to carefully disassemble your cluster and see exactly what your instrument looks like "nekkid." Then find as close a replacement as possible with the speed range you'd like.

Take a look at the second pic; that is a "canned" instrument (similar to the one you found on eBay) that has been removed from its "can."
Note the difference in angle between its input bearing and the two "cluster" mounted instruments (the original on the right, the new one in the middle.)

I suspect that yours will look like the "cluster" instruments but I can't say for sure.

 

There's been a lot of discussion lately about speedometer retrofit options and cluster interchangeability with other XJs.

So for anybody asking about using a Seca 550 cluster such as this on another bike, I measured a spare cluster for you:

The MOUNTING HOLES are exactly 125mm APART (on center.)

The holes are approximately 24mm~25mm away from the instruments.

Hope this helps.

 

Question for Bigfitz. On the raised letters under the pilot lights, did you repaint them? If so what did you use?

 

On that bike, no. It's a brand new NOS cover.

But I HAVE repainted them successfully (on my other XJs.) I used white Duplicolor automotive touch-up paint; and "printed" them. You can also use Testor's model enamel (in the tiny square bottles.)

I got a small rubber stamp "blank" from the craft store and cut it even smaller (I think it might have been part of an "alphabet" set, come to think of it.) Then I applied some of the paint to a piece of glass, and pressed the stamp into it; then used it to "pad print" the lettering.

The secret is to not use too much paint, hence the "transfer" technique. Better to "sneak up on" the coverage you want. Do it very lightly; if they're not "bright" enough, wait for the paint to fully dry and repeat the process.