Re-re-reviving my '81 Seca 750

Don't worry, I just threw out the plugs from the last change. I keep everything.

 

Tank looks pretty good. Evaporust won’t hurt anything, so if you have it, why not? If you were going to go spend a bunch of money I would say it’s not worth it.

 

Already have it and it's supposedly reusable (if you don't spill it all over your garage floor getting it back out of the tank). And I've got your blanks I can 3D print and plug holes. So yeah, we'll get 'er done while waiting for USPS to do it's thang.

Will also be repainting my calipers and thought about printing some blanks for those to aid masking, but since I'll be replacing pistons and hardware, I may just sacrifice one set. We'll see. As you said somewhere (tank donuts?), once you start printing . . .

 

I did the full Por-15 fuel tank treatment and it came out really nice. Time will tell if it's as permanent as they claim but it looks like the inside of the tank is impregnable.

 

So, I've long wondered about the origin/lineage of the fairing on my Seca (again, second owner, and the original owner had the fairing and luggage rack added at time of purchase, not remembering details). I don't currently have good pics (kept meaning to do that all weekend), but have a couple from the hard panel sticker.

Despite that sticker, it's neither a Windjammer IV nor a Vindicator. I don't have the contoured turn signals like those.

Years ago, when I lost a turn signal lens due to and accident, I turned to this group to find a replacement and initially came up empty: https://www.xjbikes.com/forums/threads/turn-signal-lenses-for-vetter-seca-fairing.14025/ Neither @chacal nor Craig Vetter himself knew what I needed. Craig said the fairing was from after he sold the company and he'd already been getting ripped off a lot.

Eventually, I don't know how (maybe the Chicago Vintage Motorcycle group), I tracked down a pair of replacements (and sadly never updated my thread here). Turns out they match the signals from an XS-1100. I always found that interesting.

It became even more interesting today when I found this: https://www.motorcyclespecs.co.za/model/yamaha/yamaha_xs_eleven_venturer.htm

Aside from the 'Yamaha' decals, and the lower wind skirts, that VERY MUCH looks like my fairing. And now it makes sense why the lens crossed back to an XS-1100. So it looks like in the year 1981, Des Plaines Yamaha fitted up an XS-1100 Venturer fairing to this XJ-750 Seca to make it a little bit of an early sport-tourer.

 

History tells some fascinating stories...........

 

Got my BIG @chacal order today (lightning quick once I pulled the trigger) - braided brake lines, MC rebuild kit, caliper rebuild kits, valve cover and clutch cover gaskets, airbox boots, and some other odds and ends. Carbs are on their way back from @hogfiddles Summer Camp and the preview photos are MIND BLOWING. And turn-around was quicker than expected. I have to remind myself not to get too anxious to slap everything together, but to do things slowly, methodically, and CORRECTLY.

Also, had a bit of a setback in that I'd ordered some Dupli-Color caliper paint from Amazon, and got the calipers all prepped today. The can felt a little 'light,' but I didn't think to much of it until I went to spray and . . . nothing. No propellant in the can. PITA to get a refund from Amazon, but finally did. Will pick some up locally instead.

Things are coming along, and I hope to have a running engine by the weekend. Still want to get the gas tank rinsed out with some Evaporust and spot-clean the engine a bit while I have the carbs off and things are accessible. Bought a new toilet brush - my cleaning weapon of choice, some purple Simple Green, and already got to work on the valve cover. Need to strip some of the remnant clear-coat, though. Not planning to get things spotless before I get her on the road, but want her presentable. Have to live up to those 'new' carbs.

 

Carburettors look like new.

 

When I say I was shocked . . . Spousal Approval Rating is high as well.

 

Carbs showed up a day late today, but it was OK, I still wasn't ready for them. They look amazing. New battery also arrived. Did get both calipers painted and rebuilt over the last couple days. Though I sprayed both at the same time, one came out glossy and the other more matte. Not going to fret it, they look way better than they did. Also got the master cylinder cleaned up, but did not embark on the rebuild yet.

Also used airplane remover to get the unclear-coat off the cam cover. Going back and forth on more prettying or slapping it all together to make sure she's still a runner and saving more detailed cleanup to the off-season. But while I have easier access with the fairing, tank, and carbs off . . . Nah, I want to hear her run!

Tomorrow after work is pretty hosed, so probably be Saturday before I can test fire it.

Moving along . . .

 

Could someone (@chacal ?) advise how to replace these? My guess is the original rubber is so hard, it's a physical impossibility to easily remove them and they must be cut off, then the new ones will slide on fairly easily, perhaps aided by silicone grease. Can someone confirm or correct?

Thx.

Hoping to get the cover and carbs back on in the morning for a test fire.

 

Oxy-acetylene torch is a good method; if one isn't handy, a jaws-of-life will work in a pinch, too......



Or you can do it the e-z way:

https://www.xjbikes.com/forums/thre...-tool-now-with-how-to-pics.40308/#post-351301

 

I tried searching, I promise. I should have been looking for donuts. Mmmm, donuts.

Thx for the speedy reply!

 

I used the end of a tube of caulk to make a substitute donut tool. Used a pair of tin snips to remove the old ones.

 

I 3D printed a thing, but I won't get a chance to test it out until probably tomorrow.

 

This morning I got the pressure washers changed, did the car boot wrestling match, and she fired up on the first try. Need to dial her in of course, but so grateful to the great work by @hogfiddles getting the carbs right in the ballpark. Details later.

Instantly thought the engine was grenading itself, but then remembered I left it off with a pretty bad rattle in the exhaust collector. I feel like this was a known issue? Just ride it until it gives up?

 

So, after that excited post . . . it was a really up and down day with the ol' girl. First, those pressure washers . . .

Weapons of choice - and those 4 inner ones needed more persuasion . . .

A little wiggle with the Vice-Grips got 'em.

And just how hard that rubber was after 41 years.


My 3D printed guide tool was the business:

(I uploaded the files in the 3D Printer Files forum.)

I had my first 'oh shoot!' when I started cross-threading one of the bolts. Rule #1 of holes - when you find yourself in one, stop digging. I backed the bolt out, cleaned up the bolt and hole with tap/die and got it in straight. I went really easy on the torque. I'll keep an eye on that spot and if I have oil seepage, I'll do a helicoil.

I then moved on to re-mounting my refreshed carbs and fighting the airbox boot fight. I know old boots have a bad rep, but the new ones were tough because they weren't sure what shape they should be in and were pretty happy to just flop around. But I eventually got things buttoned up.

Installed the new battery, double-checked my oil level (had drained out the old stuff a couple weeks ago), and gave her hell. As I said in my prior post, she pretty much started right up - second button-push I think. I was elated (and made that post).

After that, things started to get a little frustrating. I went to sync the engine and couldn't get good readings with my brand new CarbTune Pro as discussed here. Did the upside-down thing and got them lined up pretty good, but as Len mentioned in that other thread, that shouldn't be necessary. I should have stronger vacuum. So I don't know if I have a problem with my intake boot ports or what. Didn't even bother trying to ColorTune, since I could not really get idle stable. I later started to suspect the cheap aux fuel kit I got isn't giving reliable fuel flow. But I'm also starting to get suspicious about the intake boots.

With that, I gave up on the engine (it was getting hot) and moved on to my brakes. I'd rebuilt my calipers the other day, but just got them mounted up today. I also started installing the new braided stainless lines but ran into a problem with the right side anti-dive hose I need Len to help me work through. I polished a few bits and bobs and called it a day. A decent but somewhat frustrating day. Slow and steady, though, I'll get there. Aside from the tune and brake line, the other big thing is putting the master cylinder back together and getting that piped in and eventually bled.

Good tired tonight.

 

Here's a brief video where I was nice enough to block it the underwear show my buddy didn't bother telling me about.

And you can hear the collector rattle. I've read a few threads on it and will check on the usual suspects like heat shields next time I'm working on it. I do have a mechanic's
stethoscope.



And it's hard to make out, but I mentioned an old mouse nest blowing out of the left tailpipe. I hates those meeces to pieces.

 

I had one where the gasket between the collector and the muffler was bad - causing a rattle.

 

See here for the documentation of my battle with a rattle-y exhaust and figuring out the gasket:
https://www.xjbikes.com/forums/threads/xj700n-exhaust-collector-to-can-gasket.130066/#post-659791

This was an XJ700N, but the gasket is the same.