XJ750 Seca / XJ650 - Build - Up and running!

Hello
Thought I would share my latest project (mild custom and hand made bits) as it gets to some semblance of completion. This is my 1981 750 Seca frame with my 1980 650G motor. The 750 motor needs a top end rebuild, so the 650 will work for now. I actually prefer the non-YICS engine, so the 650 may get a bore and rebuild, not sure yet. Lots left to do, but it's up and running for now. Went for a good ride tonight, so that's a plus!

Lots of help from this forum and parts too!! Really great service from Chacal.

Here are some more pics with a grocery list of things done, and things left to do!



Things done - Mechanical:
-New clutch / New front and rear brakes (dual stainless steel lines on front).
-New cables / plugs etc...
-Rebuilt forks / seals / anti-dive units / front wheel bearings / swing arm bearings.
-XS 850 front wheel / Maxim X or Virago (?) rear. (Have a set of Virago wire wheels also, but need a different front end - future project).
-Carbs very, very clean - all passages open.
-Valve shimmed to spec / carbs synced / compression checks out




Things done - frame, electrical, and other bits:
-Reworked the rear frame rail with trapped nuts
-All steel rear fender with taillight inset
-Bobbed front fender
-Fiberglass side covers (will do for now, but future plans to integrate the design with the air-box a bit more).
-Aftermarket upsweep mufflers (nice tone out of these).
-Wiring completely new, redone new front to back.
-Relocated ignition switch to left side cover (kill switch still on handle bar)
-Bullet turn signals / LED flasher wired in place of OEM unit for the amp drop



-Tail light (Honda 50? Not sure swap meet find) Tailight guts and backing plate fabricated from an old indicator (dual filament) socket and a piece of plexi. Still need to make an aluminum shroud (cover) for the taillight.



-Custom made leather seat / aluminum pan (first try, probably will stitch another cover over the winter and remodel the rear hump).



-Handle bar swapped for standard low pull backs.
-Swap meet find headlight and stanchions.
-Mini speedo and tach / Fabricated aluminum bracket.
-New after market brake reservoir matched to a (CBR? Throttle assembly for brake lever clearance).



Next up is to finish enlarging the tunnel of this XS tank and fit it to the bike. That's a winter project. Probably a heap more things I'm forgetting as well.

Thanks for looking.

--------------------------------
1980 XJ 650G
1981 SECA 750

 

Very nice.

 

Damn, now that is a well thought out and done custom XJ, prolly one of the nicer ones here. Bravo.
Quick question, how well can you see the faces of those gauges? From the picture, it looks like they are pointing upward rather than facing the rider. Anyway to put a bend in the bracket you fabricated? I did something similar with my old 883 and while it looked nice having the speedo tucked down on top of the headlight, it drove me nuts not being able to really see it.
Also, where did you get the pipes?

 

Well done! It looks awesome

 

Your mufflers look like Norton Commando replicas I saw on MikeXS650 website.

Very nice work, by the way!

Your rear wheel came off of a Maxim-X, no doubt.

 

Thank you! Lots of hours to get to this point, and lots more left!

 

Thank you! Appreciate the comments.

I'm a bit taller of a rider so no problem scanning the gauges. Part of the setup was sitting on the bike and measuring everything to fit. The seat is lower as well so it all seems to line up. The gauges were originally higher and further apart. Check the bottom of this page: XJ Forum - Speedo / Tach They are also stupid bright, so I may put pieces of light window tint on the dials.

I actually have to tilt my head down on my 1200 to see the speedo (that's another project in the works).

Mufflers are MikesXS, not sure if they are the Norton knock offs or the cheaper generic.... without checking the bills I'll say the cheaper ones

 

Thank you, lots left, but that's part of the fun!

 

Looks good.
I think you'll need a Maxim or Virago front end for the wire wheels.

 

Thank you! Lots left. XS gas tank and seat rework this winter. Also have some small hard bags (18x12") that may get fitted for more fun grocery shopping trips. (minus those massive indicators!). Then overall bike paint and cosmetics.



Yes, MikesXS for the pipes, the Commando Style Universal Megaphone Muffler. Bit of a pain to fit with the reducers, so in the works are one-piece stainless 2-1 headers to mufflers (both sides) with a removable horizontal cross-over for easy disassembly. That will lighten the load of the clunky OEM cross-over connector underneath. Future project, will happen with an engine tear-down/swap. This engine is fine so perhaps after next season of riding.

Good to know about the Maxim-X rear wheel. Got it from a Virago guy in Calgary AB while delivery some carbs. It was a "I think that will fit and looks cool purchase, and it did! haha!)

 

Indeed, I'm looking around something will come up locally eventually. A front swap my be in the works. I find the Seca anti-dive front end a bit heavy, although it works well, but an XJ750 front end with Progressive springs would most likely get the same effect. I do have the 650 frame so the wires may go there. Possibly a YZF-R6 front fork (or similar?) swap....mmm options from the parts pile. One project at a time!

 

Some info: The 700Max and Virago front ends interchange and they are longer than the 650/750 Max/Seca front ends. You also have to consider if the single or dual brake front ends will accept the spoke rims and spacing.
Have fun! Like the spoke rims though.

 

Hi I have an 82 seca 750 and I'm looking to swap out the big ugly rectanglevgauges to something like yours. How difficult is it to wire that to work? What do I need, and what gauges are those?

 

She's a beauty. Well done!

 

It is a bit of a job no doubt. This post here explains the work needed.
http://xjbikes.com/forums/index.php?threads/34143
Well on my way for parts collecting, just need to find a front end locally. Although I do really like the straight spoke cast wheels on there right now. Mmm another bike build for the wires? Perhaps.

 

Thank you! Some more cosmetics, gas tank swap, and heaps of engine polishing to follow. After a bit of trouble this week with one of the coils and poor idle (air/fuel mix and a re-snych), I got it all sorted and put in a 60 mile highway ride with a group of friends. Ran strong and fast, the 650 engines always surprise me when they are dialed in just right.

 

It's not too difficult with a bit of basic solder/wiring practice. Wrapping your head around the wiring diagram etc... is probably the hardest part. The most important bit is to add diodes to your existing signal wires because the mini-speedo only has one indicator bulb. If you don't add diodes both indicators will flash at the same time. Diodes are directional specific and block current from flowing back. I also replaced the factory connectors with Molex connectors. This keeps all the wiring clean and detachable in the headlight bucket. Again pretty easy to do and connectors are available at an electronic parts specific store. You could use basic auto store ones but Molex is way tidier.

I went the cheap route, but there are lots of choices out there. I made the bracket out of aluminum which you can cut with a hacksaw or jigsaw and file, sand, and polish for nice results. Here is a couple setups on this forum: http://xjbikes.com/forums/index.php?threads/43811

Ok some links to get you going.
Wiring diagram:

Mini-speedo and tach:
https://www.mikesxs.net/products-46.html
:!: Important here. Make sure you get both units as LEDs otherwise the light won't match. As in incandescent and LED mix. They aren't marked too well on the MikeXS site.
:!: Make sure you get the right ratio for your application. Mine work really well, but lose about 5mph between 60 and 80 mph. No biggie and may save you a ticket !!
:!: Also these are un-openable units (at least not without some creativity) so LEDs just make sense.

Diode examples/discussions:
http://www.triumphrat.net/twins-technical-talk/72383-mikexs-speedo-installed-light-help-2.html
http://forums.sohc4.net/index.php?topic=71144.0
http://honda-cb750-s.456789.n3.nabb...o-with-indicators-install-DOHC-td4029441.html Image near the bottom.

Drag Specialties Install sheet:
http://www.jpcycles.com/instructions/pdf/5600262.pdf

There may be more on this XJ site, but the above is from my collection when I was researching this job. Totally worth doing, lots of help available if you run into a snag. Go for it!

 

How difficult was it to swap for those round gauges ? I have an 82 seca and I'm looking to do something similar. What kind of gauges are they?

 

Um... the post right above?

 

LOL....This is fantastic. Thanks for making the time for such an in-depth post. I had a lot of questions around this and this ticks all my boxes.

 

LOL....This is fantastic. Thanks for making the time for such an in-depth post. I had a lot of questions around this and this ticks all my boxes.

 

Cool, lots of info out there, fun trying to figure out how stuff works!

 

A quick update. Its been almost two months of fun time thrashing with the XJ. The riding weather here, in middle of nowhere officially called "the gap" best drive through at night so you don't die of boredom by the rest of Canada, has been really good. After a few gas, filter, sync, and mixture gremlins (mostly caused by tank sediment is my guess) the XJ has been running like a champ and has logged over a 1000km (620 miles) hassle free (and no tickets! despite power to spare). The main issue is I don't get to ride it that much as it has become the new 1st choice loaner bike on ride days. Oh well, I get to ride my Sporty more.. Think I'm going to have to name the XJ: Hōrō-sha (loosely translates to tramp, wanderer... well you get my drift). All the cosmetics, gas tank and engine swap and such are going have to wait until the winter.... she's busy now. Here's a few images.




Learner riding buddy (Hugh) taking a break from doing an amazing job at keeping the rubber side down!


And yes we do have paved roads here in the developing nation of SK, but phhhbbbt who needs that when you have gravel and open fields!
(Note actual paved road with signage in background!).

 

that is a great looking bike
congrats

 

Thanks! Although that tank has to go... XS tank in the works.

 

I have been looking for a Fabricated aluminum bracket just like what you have... any chance you made 2 of them??

 

I want to buy bike for my son and want to know which top motorcycle brands are. I want something good, which doesn’t consume a lot of gas and its maintenance should be also on lower side.

 

any better pics of your ignition relocation?

 

How hard were the XS850 and Maxim-X wheels to fit the 750 Seca?

 

That aluminum bracket was made by hand. 1/8 plate. jig saw, drill press, files and elbow grease. Next time I'd bump it up to 3/16. I don't have #for the type of aluminum, but it was cut from an old highway sign. I highly suggest you give it a go, not too difficult.

 

I can post some some soon. We have piles of snow right now and all the bikes are wrapped up in the storage shop. This is an in progress image. It was just a matter of fabbing a bracket. Not sure if I moved a relay (might have), and extending wires. I think I mocked it up about three times before it sat right.

 

Almost straight bolt on. I think the front needed an additional axle spacer, about 1/2" I have a box of bits collected from many boneyard trips so I just used an odd spacer cut down. The rear drum and brake stay are from a Virago. I don't think this is an issue with a 750 frame. but on a 650 frame the back brake is smaller so you have to upscale to the larger drum.

 

If your rear wheel has 5 spokes it's either virago or 700NON- X. If its wider-it's virago, if its narrow like the rest if ours it's 700 NON-X.

If its a cast rim that's almost solid but with a few tiny windows THEN it would maxim -X.

Maxim-X



Virago



700 maxim NON-X

 

Not sure, but I think it looks an awful lot like this 1985 XJ700-X rear wheel

 

Yes, that is an X rim. It's viewed from the brake side. The pic I showed is viewed from the final-drive side.