Should I go for it, or should I run?

Just looked at a 550 Seca for $300.

Paint is rough, but brakes are good. Won't start, but cranks over. Clutch is badly out of adjustment, couldn't hit neutral and it kept trying to move even with lever all the way in. Throttle cable is disconnected and gas is pouring out the air filter. No gas in oil, though...

 

Buy a compression gauge,check it.Remember,pull all the spark plugs,disconnect the TCI,take some string,tie it to the bracket where the throttle cable fits and pull it up.
If the battery is dead jump it with the car ignition off. If the owner won't let you do it or do it himself...forget it. Just about anything else can be fixed by you.

 

Buy it and if nothing else part part it out if it's too far gone to fix up.

MN

 

Well, I got it. Came with a spare rack of carbs and a spare exhaust and a bowl of bolts. This spare rack isn't anywhere near as crusty as the one for the 750, but the PO already started on it, so the jets are messed up. I'm not sure what the numbers on them are. I don't know that I want to work on that. Maybe later.

The carbs look different. Are 550 carbs Mikuni?

 

yep 550 uses the mikunis

 

For that price with the spares you did good, but sadly it does sound like it had bad foster parents. It's going to need some serious therapy from you. You will find several differences in the 550.

 

Welcome to the Dark Side.

Lots of little things are different on the 550s; the clutch innards, chain drive, and the marvelous Mikunis. And the neutral switch is actually accessible.

Mikunis work on the same principle as the Hitachis, but they're constructed somewhat differently. They're a little more "finicky" to work on, but IMHO they're a better instrument than the Hitachis.

Basic Mikuni exploded view w/pics: http://xjbikes.com/Forums/viewtopic/t=31061.html

What year Seca? If it has stock paint anywhere, white='81, red='82 and black='83. You can't go by manufacture date.

Quit trying to start it and get a compression test. Then get some oil in the cylinders (if you didn't need to do a wet compression test) and get the carbs off. At the very least you've got a stuck float.

Good find. Let's see a pic or two.

 

Title says it's an 82. The one side panel has some red peeking out from under flat black, so it might really be an 82.

Switching to ON from PRI got gas to stop leaking, so the petcock appears to work.

The front brake line is braided stainless, which is kinda neat.

I can't read the numbers on the main jets on the spare carb rack. Were there different ones, or is it a good assumption it's the right carbs?

 

Clutch plates could be stuck together if sitting a long time. You try rocking it back and forth hard in gear? Sometimes they pop free....

 

You have a 50-50 shot.

While all the 550s, Seca and Max, were basically mechancally identical; they had some different carb internals.

The pilot air jet and main jet needles are different between 550 Maxims and Secas; the mains the same. I'm not sure quite how you tell the needles apart (that would be a chacal question) but the pilot AIR jet in the Seca carbs is a 170, and in Maxim carbs, a 165.

That would be your best identifier. I looked at both of my spare racks, and there are no model designators anywhere. My NOS spare carb is marked 5K5, therefore Maxim. (Seca=4U8.) But I see no markings on the as-delivered racks.

 

I'm pretty sure the clutch is out of adjustment. Clutch cable being routed outside of fork and frame is a good clue, I think.

 

I'm thinking I'm going to pull the carbs from the bike. They are clearly not functional now.

I'm not sure I want to go into a total rebuild of them right now, I still have to finish the 750 carbs which are spread out all over my bench. I think I will try to clean them without breaking the rack and without buying extra parts, if possible.

 

Does it have lower-than-stock handlebars on it? Fairing gone?

How many parts are required will depend on what you find once you get in here. You may only need some tiny o-rings.

 

Dunno. I am not sure what the stock ones look like.

Yep.

Yeah, I'm sure... The 750 rack needed all rubber except for diaphragms... And some screws... And gaskets

 

Get us a pic of the bike and I can tell you about the bars.

Like I said, Mikunis were made better; you might be surprised.

 

When I get home. I'm at work now.

 

Here is a picture. Note the light gray clutch cable.

 

What's up with the front fender. Looks like its way up in the front.

MN

 

Yeh, those fork legs are wrong.

 

Wrong like "not from this bike" wrong? Or "put together not quite right" wrong?

 

I took another look at it. I think I know what it is. The fender is on backwards.

 

looks like correct legs wrong fender its a 650 fender isn't it

 

holy balls thats what i call a dumb PO....

nice score on the bike though!

 

The fender is not on backwards.

It's a Maxim (550/650) fender; the Seca and Max have different forks. The 550 Seca fender is the same as the 650 Seca.

For '82~'83 the bike should have a body-color fender on it.

Those are not the stock handlebars, hence your clutch cable issue. A 750 Seca cable works well with low bars on a 550 Seca, it's what I'm running on both bikes.

Those are Maxim mufflers too.

 

Yeah, those forks look right, the fender is the wrong fender. Your's should have a pretty wide-spread "V" on each side that goes from the edge of the fender down to the bolt holes.

You need to get the clutch cable bracket, which will direct the clutch cable behind the 4th exhaust pipe and then it goes up through the center area of the triple tree with the rest of the wires and cables.

The rear turn signal is hanging where the helmet lock should be. The turn signal should be back closer to the rear fender.


The seat strap? Looks like it was grafted in from a Honda, but maybe those WERE present on some of the 550 secas......I just don't remember ever seeing on.

Nice find, and I'm sure you'll be able to do it justice. Tell fitzy to watch out.....your's might become a contender.

Dave Fox

 

I have a second exhaust with it, which is probably the original Seca one. It's painted black and mufflers rattle.

The turn signals are interesting. Square in the front, round in the back. I think this guy might have had a Maxim and mixed and matched.

 

you should have square turn signals at all four corners

dave F

 

It does look that way. That's an original 550 Seca seat strap. The only "bracket" for the clutch cable on the 550s is the one at the lower end; the cable goes through a wire "loop" on the frame to guide it between the #3 and #4 headpipes.

JPaganel, PM me with your email address and I'll send you the cable routing diagrams from the factory book. I'll also indicate my recommended re-route of the throttle cable because of the lower bars. The only real solution for the clutch cable is a shorter one.

 

I just reinstalled the clutch cable. I found the hook on the frame, it looks fairly decent. Also, clutch works now.

Found a few more interesting things. The wire to the starter was loose. The fusebox is awful - three out four clips are broken. I think I'm going to start a thread for inherited bits for this bike.

I also pulled the carbs. Here is an interesting tidbit - when I turned them over and some gas poured out the color of gas was different in each carb. It was dark brown in the #1 and got lighter in #2 and #3, with #4 being crystal clear. I suppose that means #1 is plugged and gas in it is old.

I checked the pilot air jets in both the rack off the bike and the spare rack. Both are 165. I'd have thought at least one was original to the bike, and should be a 170... Anyway, it should still run with the Maxim carbs, right?

 

As long as you change the pilot air jets and main jet needles over to Seca parts, sure.

The reason the carbs are different is because the 550 Seca and Maxim have different CAMS. (Seca's are "hotter.")

I wouldn't run a Seca motor on Max-jetted/configured carbs.

 

:idea: see your new thread. It might not hurt to check and be sure it's a Seca motor and not a Maxim transplant.

Check the "shorty VIN" on top of the transmission housing. If it's a "4U8" at least it's a Seca motor. If it has a "5K5" motor then it came from a Maxim.

 

It's a 4U8.