Just bought an 81 XJ550 Seca

Just dropping by to introduce myself as I know this website is going to be a huge resource for me as I begin this new and challenging chapter of my life.

I'm hoping that you, my friends, will help me cope with my situation.

I just bought an 81 550 Seca for $350 and have never worked on a bike over 125 cc. I have a compression test kit on the way. Previous owner said compression was 150, but didn't specify what cylinders had that measurement. He said he cleaned the carbs, but the bike would not run without the choke fully open. Even after warmup, closing the choke would cause the bike to die. I haven't seen it run.

When I went to see it, he was charging the battery and we put the weak battery in the bike with the charger on. It didn't start, but turned over alright.

It looks okay, but is missing one side cover and they removed the air box I think. They also chopped the mufflers down. That looks bad and I expect it to sound worse.

Electrical looks good and I believe all lights and horn work.

Tank has a couple small dents and a little rust inside. Needs new tires, though they're holding air.

I wanted a project, because I only learn through experience. I know there are some really excellent teachers here and I look forward to scouring past threads and probably starting a few of my own. I know a little bit about bikes, but have a lot of gaps in my knowledge, so excuse me if I ask stupid questions!

My name's Ian and I live in Yakima, WA and am in Seattle often. Hope to meet some people in the NW to get together with!

Happy holidays everyone!

 

Assume that he didn't clean the carbs.

Welcome aboard.
Your first reading assignment follows.


http://www.xjbikes.com/forums/threads/the-information-overload-hour.27544/

http://www.xjbikes.com/forums/threads/in-the-church-of-clean.14692/

The local partsman can be found by clicking the logo that resides in the upper right hand corner of every forum page.

 

Welcome aboard.

Gary H.

 

Welcome, you are in a great place to find resources on old bikes. Man I wish I could find a 550 Seca for $350.

 

Thanks guys. Well it came last night and first thing is the front brake had seized up completely.

I knocked it loose with my hand and got it into the garage. Overwhelmed, so gonna keep my hands off it while I do some mandatory reading as linked above!

Pics!

 

WOOHOO


The coveted white version of the 550. Are you going with air pods or do you have the original carb parts?

I would assume that he didn't remove the jets and clean them. So the small pin holes have gunk in them.

 

need a battery BikeMaster AGM Platinum II Battery MS12-12A-4A1 $62 free shipping
http://www.ebay.com/itm/231632960576

I just got one yesterday and it showed up today ships from NY

check your valves and compression first before spending any money.
then ohm out your ignition system
coils, spark plug caps, pickup coils.
motor first before you start spending money.
once you know condition of motor you can start cleaning carbs
do you have a factory service manual?

that side cover is about 200$ IF you can find one.
the roads must be littered with the right side cover
starter a conversation with you check your in box

http://www.xjbikes.com/forums/search/468876/?q=Bigfitz52&o=date&c[node]=21&c[user][0]=3404

 

+1. It's a good looking platform. Spend the time and $ to make it a solid and safe road worthy runner; then make it pretty.

Gary H.

 

Thanks for the great advice!

Yes, the PO removed the air box, so planning to order some pods on ebay. I measured the port and it is 2" diameter. I suppose at some point after checking valves and compression and just seeing where I am, I'll need to see if the jets have been changed at all. I'll look around to see what the recommendations are for upjetting after pods and the baffles on the exhaust being cut back.

Thanks and great tip on the battery. Looks like it needs a new one. I measured the voltage after charging it this morning and got 11.5 volts, which looks low. The water level is fine and I am going to let it charge on 2 amp for the rest of the day and check again.

Guess, I'll just go with an exposed battery... $200?!!

Thanks, that's the plan! Though, I might try to fix the tank up a bit as I'm gonna have it off to get rid of the rust inside. Swap the bars for drag bars... That's really all I want to do at this point. But definitely want to get it running and road safe first.

 

If you are going to use pods, get yourself a set of the airbox boots to use with them.

 

I have seen a video where the guy put the sealed battery (AGM) in the tail section behind the seat on his seca, cleand up the whole area where it used to be. It is not the stock size and shape battery


also has a video on side panels from an xs 500

 

These what you are referring to:
http://perfectmotorsmarket.com/maep_products/yamaha-seca-xj550-airbox-to-carb-intake-boots/

Boy, having done some reading, I fear for myself, being that I'm already without an airbox and moving in the direction of pods. Probably gonna be an uphill battle. If ever I were going to recover an old airbox, now would be the time... though this thread scared me, and then gave me hope when "Hired-Goon" chimed in.

K-moe, what is the advantage to using the boots rather than just putting the pods directly on the carb air intake port?

Reading through this post, "And Chacal.... Yes, tubes have been used with pods. To get around the restrictive lip inside some pods. No performance difference was noticed IIRC." Just curious, as I don't really want to to spend the money if I don't need to. Jobless for the time being, though interviews are scheduled for after the holidays!

Nice, I've seen a lot of videos of stripped down 650s that have the battery pretty well hidden. They look good, but that's down the road.

Getting ready to order a battery now and some tires. Thanks for the ebay link!

Looking at the Avon AM26 for tires. The bike currently has a 90/90/19 front tire, but I've seen others going for the 100/90/19. Any advice of which one to get?

 

http://www.discounttire.com/dtcs/infoTireMath.do

 

Ok, so we're just talking a bit of height and a bit of width. Actually based on price and a bit more reading, I think I am going to get the Kenda K657's with the 110/90/19 front tire. Shipped free coming in under $120. Hopefully, in the future I can upgrade to some tires better for higher speeds, but for getting started (and the price point) they look like they'll work.

Edit: I read that a 120/90/18 tire will rub on the chain guard. Should I go with a 110/90/18 on the rear?

 

If your gonna restore it, do it right: get the correct airbox, and the carb boots. After the carbs are done CORRECTLY, and the valves are out back in spec, you'll have saved yourself from an immense headache of trying to tune to pods. The rest of the bike will be easy to do, and you'll have a sharp bike when you're done

 

^^ What he said.

To answer your question about the airbox boots and pods: the boots are shaped velocity stacks, and the key to getting the Hitachi carbs to perform well is to make sure they have smooth airflow and sufficient velocity.

 

Anyone got an air box and boots they wanna sell? Haha.

I think that sounds logical. Hopefully vanity doesn't push me in the direction of shooting myself in the foot by going for the pods.

So, I popped open the master cylinder because the front brake is not disengaging. It had a bit of gunk, so I'm guessing that small hole in the bottom (can't remember what it's called) is plugged up.

I realized I don't have the stock master cylinder. It should be 1/2", but the one on mine is 11/16". It's not the same one as the XJ750, but the same bore size I think.

Now, as I understand you need the correct ratio between the MC bore diameter and the caliper piston bore diameter? I've read you can go with a larger MC, and improve your braking a bit, but isn't this kind of a big jump (1/2" to 11/16")?

Now I am wondering if I have the stock caliper on there as well. Does anyone know how to determine if the caliper is stock? Thanks!

 

A good close-up picture (or two) of both the m/c and the caliper will allow us to help identify them properly.

From the first picture up top, the caliper looks correct, but it's hard to make out any real detail............

 

check this link

Air Clnr Case Assembly it can only come from a Seca
4U8-14401-00-00

forum people selling items you can post a wanted ad too
http://www.xjbikes.com/forums/forums/for-sale-trade-swap-wanted.8/

 

Thanks Chacal! I'm staying with my grandparents who don't have any internet access, so I'm stuck on my phone. Will take photos and head to Starbucks to upload them.

I have the front caliper off for a good cleaning now. Everything looks good, but I found some gunk behind the caliper piston.


Had a heck of a time getting enough pressure built up to push the piston out, but finally got it. Learning to bleed brakes without a vacuum tool is real fun. Haha

Thank you sir! Gonna check those out now! Also going to email the PO to see if I can hunt down to the original, though I doubt he'll know. Also, got that battery you showed me on the way!

 

I dunno, for a bike I actually prefer to use the the old fashioned bottle & tube method and leave the vacuum bleeder for the cars. To each their own.

 

I gave it a try and did make progress, but kept knocking the bottle over because my tubing was too stiff and jolted the bottle. It worked though, I just had to get the method down. Fitz advice on beginning to squeeze the brake, then opening the bleeder, then closing the bleeder before you complete travel, and finally letting the brake handle release with the bleeder closed worked well. Up until that point I was sucking the fluid right back in each cycle.

So, I ran down to Harbor Freight and got their $25 kit. Got home and realized it was missing some components. Drove back down and got a new kit. After gas and time, it wasn't a great deal. Plus, the lady working the register told me that it happens quite often. So, now when I go to Harbor Freight I will double check to make sure the packaging has all components before leaving the parking lot...

 

Here are some pics of the MC and caliper. The MC says NISSIN on the bottom, but not on the sides anywhere. On the sides it says the word LOWER to indicate the fill line. Thanks for the help Chacal!

 

Nissin?

 

Yup, haha. I mean I am looking for an instant fix, but come on... haha

So, I am looking at air boxes on ebay and found this one:
http://www.ebay.com/itm/Yamaha-XJ-5...ash=item43e6be91cd:g:VGkAAOSwNphWW4lh&vxp=mtr

It's from an 82 550 Seca. Will it fit on my 81? Am I right that it seems to come with the velocity stacks attached?

If so, does it seem like a reasonable deal? Trying to get this on the bike before I cave and buy pods... Thanks in advance for any thoughts!

 

Caliper is correct, master cylinder is not (and I have no idea what it is from!)

 

The airbox in the pictures looks the same as the airbox in my 81 550 Seca, so I think it will fit.
Is it a reasonable deal? I don't know, I am not in touch with these prices.

Joris

 

Alright! Found two air boxes in the Seattle area!

Getting ready to pull the gas tank off to treat the inside for rust.

 

Just be aware that an XJ550 MAXIM airbox looks the same, but will not fit the XJ550 Seca frame properly.........

 

this is the part number
Air Clnr Case Assembly
4U8-14401-00-00
ask seller to confirm it
it can only come from a Seca as is stated in ad yes those are carb boots on the box

 

Great. Thanks XJ550H. BTW, I got the manual disk. I really appreciate it.

I went ahead and ordered the air box on ebay. Waiting for a front caliper rebuild kit to arrive.

Cleaned the rust out of the tank with the fishbowl gravel technique and a small bottle of Evaporust. Looks good now.

Battery is in. So, just waiting on the air box and then I'll turn it over and get a compression reading. Until then, I'm just hoping and praying.

 

if you do not have them chacal sells little brass brush wheels that fit in the grooves of the caliper to get them cleaned out.

 

Awesome. Your post just helped me figure out how to set up my petcock. There was no hose connected to the vacuum port. So I should buy a vacuum hose and connect it the manifold on carburetor 3? That port is missing a cap, so it makes sense!

"c2 or c3 it does not matter as long as each port is capped and 1 is hooked to the vac line on the petcock.
did you try to back off on the idle knob, you said you removed it and reinstalled it.
what did you use for the gap to bench sync?"

 

I've found a few plastic connectors that are not connected on the bike. Can you guys please let me know what they are or where they go?

One is the fuel gauge float inside the gas tank. I can't seem to find and place for it to connect to. I assume it should make its way up to the dash.



There is a connection behind the battery box that splits off from the wires that run to a small metal box. I'm not sure what that component does or what would have been connected here.

Here is a picture of this connector: (Sorry! I didn't realize how bad the picture was until I got to Starbucks...)



Finally, this black connector was under the tank. It's near the carbs on the left side of the bike. Again, no idea what it does. Can't find anything it should connect to...

 

The first two connectors mate with one-another, and are indeed for the fuel gauge and sending unit.
The second connector is for the turn signal relay.

 

Thanks K-moe. I'll try to connect the fuel gauge and sending unit when I get home. Feeling like an idiot as they would obviously connect. There may be a couple loose connections in my noggin, too... just sayin.

I couldn't see a place for the turn signal relay connector to connect. I'll do some more diggin around for it.

 

It connects directly to the relay, and the relay hangs from the frame via a form-fitted rubber insulator

 

The relay is a (rather large) rectangular black plastic box with three brass terminals sticking out of the bottom face.

 

Working through the information overload hour. Thanks to everyone who contributes to this forum. It's an incredible resource.

 

Looks like this:

 

I looked all over and couldn't find it...

Maybe it was removed by the PO.

I just did a valve reading and got some big numbers... Time to order shims correct?

In
.25
.25
.31
.20

Ex
.41
.40
.32
.47

 

What did you measure with?

 

My feeler gauge set. Bought in Korea. Metric. I might be able to get my hands on q different set to check their accuracy.

Are those outrageous numbers? I haven't tried starting the bike, but the PO tried when I was checking out the bike. It wouldn't start. He said it had previously only run with the choke all the way on.

 

If those are correct numbers (expressed in millimeters), then yes, those are huge. The cams may not even be able to open the valves much, if at all (except for the #4 intake).

 

Those are all ridiculously loose. The closest is #4 intake, which is 0.05mm loose.
It's really uncommon for the valves to wear loose (but it's not unheard of), and I can't imagine that you could get enough carbon buildup to make the gaps that wide.
So the question is, how did you go about measuring?
I just want to confirm the accuracy of your results.

We can't tell you what shims to get until you pull the shims that are there.
The full check/replacement procedure is covered here: http://www.xjbikes.com/forums/posts/122016/

 

I just used my grandfather's set and got similar results +/- .03.

I'm measuring with lobe pointing 180 degrees from the shim.

 

Then if that's the case, somebody really screwed up on the shims. Pull them out one at a time and record the sizes for us---

 

It'll be a few days, but as soon as I have them out I'll post them.

 

So this valve job has been a nightmare. I've followed the guides and just had a horrible time. I could not get the valve to stay down with the zip tie method, so ordered the tool. The tool was super hard to get "centered" but after resetting it over and over I finally managed to get all but the last shim checked. The last one will just not set properly. I've tried 10 times with the tool and it will not center. I'm pretty frustrated and that's probably not helping. So, I decided to try the zip tie method once more and first time half of the zip tie broke off and is now down in the combustion area... Wow. Didn't see that coming. I'm really not happy and am wondering if I need to tear the whole engine apart to get that zip tie piece out... Will it just burn up and be ok?

Edit: I tapped the shim tool with a hammer and it finally centered it. Every time I tightened the bolt on it, it would tile and then not work. So, yeah if you give it a little tappy tap back in place you might save some time.

Have checked all of my shims and will calculate which ones I need tonight.

 

You're not doing something right with the zipties then.....

But yes, the plastic will just burn up. Or, you can rotate til the piston is near top, the suck it out the spark plug hole with a vacuum