yx600sc radian wheels on a xj550rj seca

the purpose of this thread is to chronicle my efforts to put radian wheels on my 550 seca. this will include a fork swap from the same radian.

to start off with, I have one 1982 xj550rj seca...



pretty isn't it? then I had the opportunity to get these wheels and various radian parts...



the fork tubes are 36mm, so I had to come up with a triple tree and discovered that the radian has the same head tube length as the 550. perfect! but I didn't like the rust stains from the rubber handlebar mounts. luckily the xj650 head has the same spread and offset but has solid handle bar mounts.



to be continued...

FU

 

the radian triple tree with the 650 maxim tree top...



next, I had to find a fender because there was no fender in the bins of parts. so the search was on. radian parts are somewhat rare, especially front fenders. I managed to decipher that fzr600 fenders would also fit, as will fz600 fenders apparently.



I really like the look this is leading to. at first I didn't realize that the wheels are both 16 inches versus the 550's 18 inch rear and 19 inch front. I can't wait to see this project finished.

brakes, let's talk about brakes. aside from the addition of another rotor and caliper up front, the radian got bigger rear brakes than the 550 seca. seems logical you think... not really, considering that the 550 maxim got the same size rear brakes the radian got. I guess you would have to ask the engineers that designed it that question. especially since the 550 seca got hotter (more lift and duration) cams than the 550 maxims. it's water under the bridge at this point I suppose.

now I have to consider a gearing change too, since the rear wheel will be 2 inches smaller than the original. sigh... I haven't begun to wrap my head around that one. I am thinking larger front sprocket and smaller rear sprocket. but just how much I don't know.

FU

 

If I remember correctly, the radian forks are shorter. That, along with the smaller diameter rims, is going to reduce your cornering clearance a ton.

With modern rubber, it's easy to drag the pegs on a stock bike. You're going to need rearsets.

The smaller rear wheel will be like going 1 down on the counter sprocket. You'll probably like it.

 

Mmmm...,, i wish i could find a radian...

 

I just went out and checked, the forks are the same length. considering that the bike already sits fairly high, the 1.5 inch drop in the front and the 1 inch drop in the rear is not going to amount to much. no worries about ground clearance.

FU

 

I wish I could find a complete radian parts bike. I want to put a radian rear swing arm on my 550 and I want a radian speedo and tach. the radian speedo goes to 140mph and is more or less a bolt on mod.

edit; I just noticed the radian tach is electronic and not mechanical. still could be a possible swap since it would be possible to wire in the tach.

FU

 

You can swap to an electronic tach. Chacal sells a blanking plate for the mechanical tachometer drive just for that purpose.

 

yeah I know that, it's the reason I said it could still be a possible swap.

edit; I am also going to figure out if I can swap just the speedo guts into the seca housing and keep the mechanical tack. it looks to me like it might be the same diameter and possibly the same mounting angle and depth.

FU

 

got my fork brace today, I can't wait to get my fender bolts to bolt this mess up and see how it looks. since the fender is so fat, I am thinking about a 130/90 tire up front.



FU

 

got my 110/90-16 tires today. this is looking to be a cool custom bike when I am done.



FU

 

I'm pretty excited to see how it looks with the Radian wheels on there. Post pics soon! You gonna sell those 5 spoke wheels, or save 'em for something else?

 

yes they will be for sale. I have three of the rear seca wheels and two of the front. the ones on the bike now have new shinko tires and all balls wheel bearings.

FU

 

All Balls! Yup!
Wish I could figure a way to get the 550's wheels on my 750. Just cooler looking than the "swirleys". Hmmmm. Add an extra brake, convert to shaft, just for the heck of it? Nope! Oh well.
You gonna do paint too, or stick with the red an black? IMO you should ditch the Seahawk and go with Packers Green!lol

 

you might be able to use virago wheels, they are shaft drive. you could go with true spokes or the straight aluminum spokes.

https://www.google.com/search?hl=en...sedr...0...1ac.1.64.img..0.13.689.JCZcEykiQxE

yes the red is going away. everything that is painted will eventually be gloss black.

FU

 

woot! I got the brake rotors today!



FU

 

Siiiiiiiiiiiiick!

 

so, I've been thinking about the speedometer and the difference in wheel size. the current 19 inch front wheel/speedo configuration (stock) is dead nuts accurate. the smaller front wheel I am planning to install will be smaller and possibly result in the speedo indicating a faster speed than actual speed. now, I will be using the radian speedo drive, is it possible that the drive has a different ratio than the one on the 19 inch wheel? if it does, then I should be able to expect accurate speedo readings after the swap.

guess I need to go fiddle with counting ratios on speedo drives.

Fu

 

IIRC the speedometer drives are all the same ratio; the different rim sizes being accounted for at the speedometer.

 

electronic don't lie plus you'll know ten other things you don't care about

 

Just be careful when first riding with the new tires. The tires have release agent from the molding process and are slippery till warn off. I have seen bikes totaled from new tires and agressive riding.

 

duly noted. I have read that on every tire manufacturers website too.

FU

 

so I noticed in another thread that hogfiddles xj900rk has the same front wheel size as the xj550rj and the same design as the radian, after a little checking, also the same speedo drive part number as the 550. are you still with me? which just so happens to be different from the radian speedo drive part number. which leads me to believe that the drives are geared for the wheel size and the speedometers are all built the same.

discuss...

FU

 

got my new valve stems today...



and of course I couldn't wait to get a tire mounted to see what they look like...



I really like the way those reflective stripes light up.

FU

 

so I started disassembling the radian forks for new seals and powder coating the lowers. wouldn't you know it, but the inside hex in the tubes are 22mm, not 19mm like my 750. so I had to break down and buy another tool.

http://www.ebay.com/itm/201318463368?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

I'm glad it wasn't expensive, like most things motorcycle.

FU

 

Have a closer look at what those part numbers mean. http://www.tangedal.no/XJ/PNumbers.pdf

I will give you that the XJ750 part number for the speedo drive is different from both the Radian and the 550.

 

thanks for the link. I guess only time will tell, when I get the bike back on the road, I will be better able to say what is what.

looking closer at the part numbers, there is a constant in all of them and that is the second 5 digits of the part number.

FU

 

so I got lucky and picked up an almost complete radian today for parts.





now I will be able to do the rear swing arm swap I have wanted to do. the mufflers are not bad either, which is another swap I have wanted to do. it has 31,000 miles on it, so some of the wear parts are about done, but the bits I need are all there. woot!

FU

 

Nice score! I remember you posting about wanting to find one, congrats. Those mirrors are horrible!

 

I can't see mirrors. all i see is gold skeleton hands. oh. yeah. uh, the rest of the bike looks good. how much else can go on to an XJ? I like the tach/speedo better than the atari, and I can't even see the faces! Let's see how "Radian" you can go!

 

Im looking for a tank for a radian. Ill pay shipping as well. Please let me know.

 

Can you re-do the radian?