another new old bike in the garage

Hey all,

So I wound up picking up an 81 750 SECA (American bike from NH) last night. Needs a few things as expected (instrument cluster, headlight, seat recover, various other bits and pieces) but the engine seems sound and has 130psi across the board (16,000 miles). I'm looking forward to tearing into this and getting the valves adjusted and running well before worrying about the cosmetics. A few pics will be posted later, wish me luck!

Marcel

 

Re: New arrival

WELCOME from TN!!!

skillet

 

Re: New arrival

thanks skillet, i've been here for a while, maybe i'll update the topic

 

Welcome!

I've been doing some changes on my bike, 750RH Seca and have some of those parts available, square headlights, instrument panel and a few others. Send me a list and I'll see what I have and maybe we can work a deal.
Bill

 

Way to go Marcel. Nice to see you have a bike again.

MN

 

Nice. Glad your back in the game. Sounds like you got the right project too, and your smart to start with the mechs before the cosmetics. At least when you get there they will all make the bike look nice and new.

 

I'm just down the road white, lemme know if you need anything, i've got yics blockoff if you need it (no colourtune or carbtune tho)

 

Sounds good guys, thanks for the support.

Krs14 I have a colortune and carb sync (well, a motion pro with bubbles and a loan of a set of air gauges ). So far no real surprises, except for one of the smaller looking cooling fins that appears broken off, no biggie hopefully.

 

When you going to post a picture mwhite74? Glad you have a replacement in the stable.

 

Here's a couple snaps to give you guys some idea the fun in store for me . I believe this bike should be pretty rare, had no idea they ever came in black... BTW ground hugger, cool avatar lmao.

I have side covers, tank has a few dings. Crash bars are going on, no f**king around this time!


Let's play spot the missing fin! It fooled me, but I don't think it'll be an issue and I didn't even notice it. Oil is coming from the valve cover, I think i'll throw the 650 cover on where she's not going anywhere.


Notice the imperfection in the engine case where the right side cover attaches? that freaked me out for a second (jb weld?), but it looks like it's just something that happened during manufacturing. PO gave me some nice allan head screws!


Here's why I need new gauges and headlight...

 

Hey guys, I guess i'll just update this thread as i fix stuff, shag it...

So far so good, just checked all my shim clearances and even though some are tight, none were under .10mm!

1 in .10mm, ex .13mm
2 in .12mm, ex .17mm
3 in .13mm, ex .19mm
4 in .13mm, ex .19mm

Compared to Maxin, all but 1 i believe were less than .04mm. if all goes well this bike should clean up pretty well. Not perfect but mechanically very sound.

 

The tank decal looks like it was borrowed from an RD250/350LC.

 

Yeah, totally... Snapped this photo at a bike show a year or so ago:

 

HEY now!

 

Love the paint scheme, tired of using that shim bucket holding tool... I may have stripped one of the valve cover holes . Switched over to using a heavy piece of wire to hold the valve over, way easier... Now to find a 265 and a 290!!! I think the top is coming off of poor old maxine tonight as she may have what i'm after...

 

Great news, got the valves adjusted and the one i was missing (290) was a straight up exchange at a local shop. Have a headlight coming from somewhere and a few leads on a new set of gauges. No stripped screw as previously thought!

The 650 (valve)cover fit like a smack in the mouth and the carbs are now off. Man o man though, what a Pain in the a$$ getting them off of the seca compared to the maxim, no space even with the airbox shoved back!

Other than that there are a few missing screws which i pillaged off of the wreck, and the intake manifolds look pretty cracked, will probably just take the ones off of the 650 there as well, ha! Just a little scared of snapping off of the carb screws as per the norm. The work continues...

 

So far so good guys, got the pipes off and they appear to be the same as the others off the maxim, and no broken head studs so far...

Crash bars are on, need a petc0ck rebuild by the looks of things... the exhaust is the same as what was on the 650, so there'll be some more swapping there too.

The final drive oil was black , if i didn't know better I would swear it was plain old motor oil. Still debating trying my luck with the intake manifold bolts...

 

Manifold bolts are off, none broke!!! The petc0ck from the old maxim looks like it will fit in the Seca tank, can someone confirm if that is a direct swap?

 

From the Fische:

81 Seca 750: 3AL-24500-00-00 FUEL COCK ASSEMBLY 1
83 Maxim 650: 3AL-24500-00-00 FUEL COCK ASSEMBLY 1

Looks like a match to me

 

Thanks mtrbikecrazy55, shame on me I could have looked myself eh!

Some more updates, got the back axle swapped with the old maxim (the Secas was broke off at the cotter pin), Back brakes look ok with no delamination. It always surprises me how little they get used!

The clutch and brake cables lubed up nicely, still looking for a straight brake pedal, but that will come.

A few pics (for you maxim-x haha!)

New pipes for for the lawnboy (some slight surface rust but pretty much dent free


some rust in the old tank


crash bars are on!


What in the name of god is this? just kidding, fuel gauge sending unit, new territory for moi!


carb buddies, (650s on the left, 750 on right) the little metal plates on top of the air jets, can i toss those??? Splitting the Seca rack should be interesting to say the least!


New headlamp, thanks trophybird!!!


touchup job on the left, to be done on the right. nothing special but it was pretty rusted after some slight Road rash


no broken studs! sofa king happy!


Spaghetti anyone!?


the 5 foot view

 

Sized up the wiring a little more, check this out!


^^^ Anything seem wrong here? Looks like the fuse on the left and the fuse on the lower right have the wires mixed up or something :S. Does anyone have a pic of a 750 Seca fuse panel i can use as a reference, or confirm that the PO made a boo-boo? Ahh the joys of buying a used bike!

Marcel

 

Just a quick update,

Got the parts in for the brakes from Len this past Friday, and got the brakes apart last night. Had quite a few tense moments getting those 32 year old banjo bolts out (NEVER NEVER NEVER use an open ended wrench!!!), but in the end i freed them all. My only beef with this bike is the dumb placement of the MC, in behind the headlight... Looking forward to replacing the fusebox and various carb components (shaft seals, etc...).

Sometime this week i can hopefully get a few pics for all the dudes who helped with parts to bring this thing back from the brink

Marcel

 

Looks like you are moving along very well on that thing.

 

Not going as quickly as I'd hoped but at this point there's no real rush .

Got the brake lines swapped out, thank god for a mighty-vac (and a check valve), now have a good firm brake lever! The problem is getting those darn wires back in the bucket!!! holy crapola! Anyone have any tips for getting all those wires back in there?

Marcel

 

More progress,

Got the bucket and gauges back on last night, best thing is that the blinkers work haha! There are 3 wires on my blinkers up front (i guess aftermarket, the colors are red, black and black/white. I had the red and black wires plugged in as per the wiring diagram, but had the blacks plugged in as opposed to the black/white (where the originals only had two wires). Last night i swapped the black out for the black/white boom we are blinking.

Still have to arrange stuff in that tiny bucket but the bike looks so much better with the new components. The carb work will hopefully be a joke (shaft seals and one choke plunger seal swap, new butterfly screws), at least i can see this bad boy running again by this weekend!

 

Great to see that the build is going forward Marcel, 'specially like all the pictures.

 

Finally into the old carbs, here's a few more pictures as i've never really seen anyone replacing throttle shaft seals, AFAIK...

Man the bits were nasty looking!


New jets and washers!


Removing the choke rod, all buffed up now!


Always remember thread locker! Don't need your motor inhaling a screw at 7K Rpms!


New fuel tube orings as well, leftovers from the 650 :^(


Still have 3 more carbs to go through, but that should get done tomorrow morning. If all goes well i can dbl check float levels and bench sync, then install and see if she'll fire up sometime tomorrow afternoon! some video will be taken of this, rest assured!

 

Well, it's running!

I'm afraid however that the starter clutch free spins every now and then, hopefully this doesnt mean what I think it does! Loud man holy crap!

It's idling though at 4000 rpms! sounds like my bench sync might not have been as good as I hoped! New manifold gaskets, throttle shaft seals, etc... should have gotten rid of any air leaks...

Marcel

 

That starter clutch spin....Is that like a loud "REEEAARR" noise just after starting? Mine does that sometimes, I always wondered if it was something bad, but it's done it for years with no other effects.

 

Nope, more like a whirrr!!! then when you let go of the button it slows and you can hear it 'catch' sorta. I know what this might mean (bad starter clutch and splitting of the cases), but I've got the 650 carcass sitting right next to it, should i need to go that far. for the first while the bike would run, idle for a second then die... swapped out 4 new plugs and caps from the old bike, and boom, revs! couldn't believe it. There's a ways to go but it's sure nice to hear progress ha!

 

Oh my, the trials and tribulations of owning a carbeurated bike...

The engine sounds great, but will idle when cooler at 1050 when the idle screw is all the way out! looks like a butterfly issue on carb number two, dang it! Got it synched but when the throttles close they don't hit hard, like it's rubbing on something and not closing with conviction, FFS!

On the plus side i got the new fusebox in (thanks Jackal/Chacal ), fits fine using one of the existing screwholes:


I've got a new brake pedal and set of mirrors lined up as well, hopefully I'll get them before April, ha!

Mars

 

mwhite74,

Is that a white wire butt connection to your red/white stripe (ignition) wire on the "in" side second terminal coming "out" thick brown? Shouldn't that "in" wire be swapped with the last brown "in" wire? If I'm looking at this wrong I aplologize.

Gary

 

Hey Marcel
Pretty clean looking installation, but you may want to put some of this stuff on the connectors, it will reduce, if not eliminate corrosion.

Pretty sure you can pick it up at Crappy tire. I bought one years ago and it's still almost full! A little bit goes a lonnnnnnnnnng way.

 

Hey Rocs,

I was thinking the same earlier when i first got the bike, but it turns out the wiring diagram has a brown wire on connected to a red/white, etc... So I'm going to leave it.

Graham, thanks dude! I actually cheated and used some petroleum jelly, which I've heard does pretty much the same thing.

I just got finished with the carbs again. One thing that i noticed was that when i pushed down on the screw it would idle down... Turns out one of the butterflies wasn't on quite right and it threw off carb #2... Anyways now when i apply pressure to the top of the sync screws they don't move, at all, so I should be good! That should be mentioned in the FAQ section if it's not already...

The only thing about carbs, you have to re-install them to check and see if you made a difference hey? I'll check back in tomorrow with some good news hopefully!

Marcel

 

mwhite74,

You are correct sir. I just looked...pg.270, Haynes Manual. I didn't look earlier. I just ASSumed yours was similar to mine. HEE-HAW, HEE-HAW! Sorry bout' that.

Gary

 

Well guys,

The carbs went on easier this time, but I think I broke it, check out this video

Seca Start...

Picking up a set of mirrors and brake pedal tomorrow night, then to wait for spring

Marcel

 

Coming along nicely Marcel. Nice work!

 

Kudos! Betty sounds nice...so nice that waiting for spring is going to be difficult.

 

Hey guys,

Just got my seat back from the shop. Cost a bit more than expected, but it's not got memory foam inserts and the color matches a bit better. Might have gone a little overboard with the piping, but I'm happy with it!

 

Not at all the piping carries the lines beautifully! I wish upholstery was something I could do, but it's an art if you ask me.

 

Thanks for the compliment Merc!

Yep, I couldn't agree more with upholstery being an art form, some of the seats they were working on were like night and day (mine included ).

 

This is what I created for carb synch

http://xjbikes.com/coppermine/displayim ... pos=0.html

This setup will tell you exactly when you have the screw set properly for synching adjacent carbs. When the fluid stops flowing you are synched. You have to have the YICS tool inserted and the lever flipped.

The difference before and after synch is like night and day. The only purchased items are windshield washer hose and plastic nipples. I used intake manifold boots to cover the bottles.

 

mwhite how's the bike coming? Finished yet?

 

Nice seat!! what did it end up costing if you dont mind me asking?

I like the look, I think im going to do red piping for my 550 seca as well