First Cafe Racer Mod! 1983 XJ750 Maxim

Uh oh, I’m replacing the bearings and the axle spacer fell out, which side does the side with the lip go on?
Ride side or left (speedometer cable side)

 

I believe you have it facing the right way, on right side, but I don’t know if there’s a difference between 82 and 83.

Go to the 8:30 mark on this video for comparison. Maybe it helps:

 

Your orientation in the pic is correct, all models, all years.

 

Thank you guys!
I have the new bearings in and everything looks good.
The lip didn’t appear to touch anything so I have no idea what's the purpose of it!

I did notice my axle shaft is not 100% straight...
Doubt that’s normal but this bike only has 14k miles...
Do they normally have a minuscule arc to them?

https://vimeo.com/user87851083/review/282163443/100fb2ff37

 

You know the answer to that surely?
Noooooo

 

That is indeed bent. Start checking the fork legs for similar damage, and the wheel for cracks.

The collar on the inner spacer rests loosely against the bore once it's installed to keep the spacer centered in the wheel for axle insertion. Without it the spacer can end up cockeyed.

 

Can there be damage to components I couldn’t see internally within the forks? I’m about to do a rebuild with Progressive springs, anything in particular that would take that kind of impact?

Checked the wheel and forks, they both look good

 

Small side track before I make a big purchase from @chacal , does this thing have a name? It’s the airline between the forks...
Can’t find a diagram with the name of it anywhere!

 

"air hose union"

This conversation covers it a little: https://www.xjbikes.com/forums/threads/removing-front-shock-air-hose-union.92803/#post-519943

I think Len is calling it the air joint on this page: http://www.xj4ever.com/catalog/k.html

I like that name better. For unspecified reasons.

 

Huge curveball!
After talking with Len, he believes these belong to a different year, they’re currently on 83 Maxim XJ750.
Len suspects they’re an 82 Maxim 750 set but the caps didn’t match the 82 example he sent me.
Anyone know what these belong to?!
I also found the forks were stamped with “Y75R”

 

Nice video.

Well, the 15R casting on the lower fork tubes is the proper tube for both the 1982-83 XJ750 Maxim tube. The long "dipstick" on the bottom of the cap bolt indicates that it's from a 1982 750 Maxim model (as does that "shared" air hose system), the 1983 models did away with that adjuster stick on the bottom of the cap bolt (a great idea, but rather finicky to use).

So I think that someone has simply replaced the proper upper cap bolt plastic cover with ones off some other, unknown-to-me (is that a known-unknown, or one of those elusive unknown-unknowns?) model. The top cap covers are somewhat interchangeable between many models.

So I'm going with "1982 XJ750 Maxim forks" for $100, Alex..................

 

Just to make sure we have the right info Len, it has Y75R, in case there’s a typo, I took the photo when it’s dark so it’s not the greatest quality..
I definitely agree with you though, everything I’ve seen so far points to an 82 Maxim 750!

Apparently a damper rod wasn’t needed as I’ve seen in the forums
I removed the top springs.
Removed the drain screw on the bottom.
I was able to separate the upper and lower forks with a simple tug!
The piece that the rod fits into appears to have been taking damage and needs to be replaced!



I’m actually quite surprised how easy this really is compared to others I’ve been reading about!

 

Anyone recognize this Spindle type?
Len doesn’t recognize it.

 

You know, the more that I think about it, it may be that someone has swapped XJ1100 forks (or, at least the guts of them) into those tubes. The XJ1100 models also used that "shared air-assist" feature, and they use a goofy taper spindle somewhat like the one you have shown (the semi-threaded hole is the clue).........the XJ1100 forks retained the damper rod via the oil drain screw, coming in from the side of lower fork tube, and threaded into the taper spindle. But that one on your bike also looks like it's been modified.....the V-cut on one side.

XJ1100 models also used that long skinny rod embedded onto the bottom of the cap bolt. Only thing is that the XJ1100 used 37mm chrome tubes (750 Max used 36mm) so those air joints for the hose wouldn't fit properly.

It's all very confusing........

 

Hmm, maybe a previous owner just ordered that Spindle part to piece together these Franken-Forks!
I wiped off and inspected the Spindle since you mentioned it may have been modified I think you’re right, it’s definitely machined!
There’s a “finish” difference where it’s tapered, it’s a little uneven, and impact grooves from the internal surface of the Lower Fork Tube.
The Spindle does have about 1 mm of free play inside the lower fork tube.
I measured things in case that helps!



The culprit= wrong Spindle for the bike!!

Once again Len, your knowledge is incredible!

 

Looks like '82 750 Maxim forks, but I think someone swapped the insides somehow. I've never played around with swapping for internals, so I don't know. It's just a guess., or maybe swapped tubes.....etc......

 

Eureka! I went and pulled a taper spindle from an XJ1100 (it's called an "oil lock valve" on the 1100's for the uber-curious) and darned if that ain't it...............although, someone has modified the one that you have, probably to make it fit. I mean, since it didn't fit, you just use a bigger sawzall, right? That's always what I do when I'm messing around with brakes and suspension and other bits that my life possibly depends on.

So, you need a taper spindle, and perhaps a dampening rod, and God-only-knows what else......

 

Or just get the correct forks

 

I ended up buying '82 forks on eBay, got the rebuild and a new tube from @chacal, everything is looking REALLY good, in a couple days i'll have a photo working picture of the front end!

Anyone know what the Ohms are on a 1982 Seca 750 gas meter sending unit are?
I know it's random but I'm double checking before buying a gauge and I would like to go digital since wired applications in MPH are hard to find or ridiculously expensive!
Also my 83 750 Maxim didn't come with a gas gauge and I'm guessing a digital speedometer/ tachometer would bring the electricity needed within a display.

If I remain analog, whats the ratio i'm looking for with our speedo drive?

 

600 ohms seems to ring a bell

 

HCP683
OEM Fuel Tank SENDING UNIT 5G2-85752-01-00
same as 750J Maxim, but arm has a reverse bend to it
Full = 25 ohms
Empty = 300 ohms
Applications:
XJ750 Seca

 

So far this is looking to be the top contender!
https://www.amazon.com/gp/product/B076KMJ525/ref=ox_sc_act_title_1?smid=A2KZ2NFQTEZSE3&psc=1

Anyone with experience using this one or switching to digital speedometer? I saw someone here is using an Acewell

This is one is nice too and uses more space on the display but $300 on a gauge is steep!
https://kosonorthamerica.com/shop/motorcycle-mx/tnt-04-multifunction-meter/

I'm trying to avoid those nice looking but cheap Chinese ones, although perfect design, they're outside of my qualifications!
https://www.amazon.com/IZTOSS-Speed...coding=UTF8&psc=1&refRID=9E2NTR8HVM8R3TW7QRQ1

 

i use a old acewell from some dirt bike.

 

Do I need some sort of limiter/ regulator for an LED headlight?
Headlight I purchased:
Power: 30W(Low Beam),45W(High Beam)
Lumen: 2800lm/Low Beam,4000lm/High Beam
Working Temp.: -40+85°C
Life-span: 30,000hr
Size: 5.75inch
https://www.amazon.com/gp/product/B071Z6JQCF/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Brackets were horrendous so I bought these if anyone was curious:
https://www.amazon.com/gp/product/B00WXZQNCE/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Incredible quality!

 

Depends on the headlight, many Led lights have the resistor built in. May need a different relay if you are using the stock wiring harness. You definitely need a new and regulator/rectifier if you are upgrading to a lithium ion battery like the anti gravity or ballistic. The charge point is lower ~14.2v compared to stock lead acid which requires ~14.8. Don't want to fry your expensive new battery. Rick's Motorsports can make you one.

 

Awesome, I was suspecting that they may have the resister built in.
I think I'm going to keep the stock acid battery and air box set up, I'll just cover them up!
So if I plug it in I'll be OK?
Electrical is where I get nervous!

I've been busy taking care of my uncle for the last month so I've barely been able to touch her, I'm excited to upload a photo worthy update soon!

 

I would definitely check the specs of the headlight you decide on, but they are generally plug n play. Look for one that is rated for use on a 12V system. Almost all of them are. Avoid eBay, you get what you pay for.

 

Update on the project now that I’m getting to it again!
I’m currently on the painting phase for the gas tank and front fender, removed all paint, did a little Bondo work, put 2k Epoxy primer to seal it, sand, another layer, sand with 320 grit.
Going to do Filler Primer, maybe 1-2 layers to fill in any pits or scratches and sand again.
Hit it with 1k base coat, 2-3 layers.
Then 2K clear coat, 3-5 coats (because it’s the protective layer) then 1500-> 3000 grit wet sanding to rid of the orange peel!
I already use Caswell Epoxy gas tank sealer on the inside too!

 

Anyone have a wiring diagram for the stock gauge cluster?
I need to figure out some of these wires on the stock setup.
I labeled their uses and figured out majority of them being ground
If anyone is interested, I purchased an Acewell digital gauge with a speed sensor adapter, also trying to "add" a fuel gauge from the 82 Seca tank I swapped out on the Maxim.
(Maxim didn't have a fuel gauge but the Seca does)
Acewell gauge:
http://www.acewell-meter.co.uk/Acewell Speedometers/ACE-MD52/MD52-253.htm?action=full&id=198
Acewell speed sensor adapter:
http://www.acewell-meter.co.uk/Acew...s - Cable Drive/ACE-S12.htm?action=full&id=25

 

Shouldn't be necessary.........

Which cluster (what year/model bike?) and/or specifically, what in particular do you want to know?

 

You guys are extremely helpful, I’m just trying not to bug you for every single wire I’m not sure about if I have a diagram saying what they are.
I tried finding one online but haven’t had much luck.
It would be cool to make a quick write up to share on here

 

sent you a conversation with wiring diagrams

 

Nice paint job on that tank, it's like a mirror!

 

Thanks! It took a LOT of work, I can see why it’s so expensive to have a professional do it!

 

regarding the under seat "pan" , to house the electrics and battery, heres one I made from ally plate, housed everything I needed ,and more,
including battery isolator , card reader ignition, and tool pouch.

 

looks cool, but you are missing the kitchen sink.

 

Look closer. With the electrics removed it can be used as a kitchen sink

 

For a modern lightweight gauge this is what I use. (ebay of course) Copy of the KOSO GP instrument. Made in China but with the same Japanese parts as the KOSO, I got that info from the guy that has them made. I have one on my 1975 Suzuki T-500 and love it. I have another for my XJ 750 Maxim when I get that far. I'm not a fan of the "Atari" thing.
Cheers, 50gary


motorcycle,KPH,&,MPH,digital,speedometer,yamaha,kawasaki,12,000 rpm

• ITEM PRICE:US $57.52*Converted from GBP 44.77+US $3.84*Shipping: Converted from GBP 2.99
• TIME ENDS:Mar-13,09:35 AM PDT
• SELLER:littlethingsuneed(11267)Feedback score is 11267 for littlethingsuneed99% positive feedback
• * Converted from GBP 44.77 (+GBP 2.99)30 watching

 

I’m finally back and I’m working on upgrading the gauge!
The Maxim doesn’t have a fuel meter but I swapped out for an 82 Seca tank that does!
I really want this to work with the gauge I bought!
I chose the Acewell MD-052-253, bought an adapter from Acewell to convert the stock analog speed cable to digital as well!

 

does you. r wiring diagram give a spec on the fuel guage resistance it will work with?
there is an older thread that discusses Yamaha fuel level sensor and its resistance you can measure it easy enough

 

I found the previous owner spliced some ground wires and made it confusing for me why one turn signal has a single hot wire when the other had 2 ground and a hot...

My new LED turn signals need a Ground, is there suppose to be a ground on both sides???

 

Yea, Chacal chimes in with the specs on the fuel gauge sending unit awhile ago.
“HCP683
OEM Fuel Tank SENDING UNIT 5G2-85752-01-00
same as 750J Maxim, but arm has a reverse bend to it
Full = 25 ohms
Empty = 300 ohms
Applications:
XJ750 Seca”

 

http://www.acewell-meter.com/wp-content/uploads/2018/04/ACE-MD52-ENV1-20171123.pdf

looks like they have a switch for low to high or high to low

looks like you want to select the 250 ohm setting

 

Thank you for looking into that!
I didn’t even get to that part but you just saved me a future head scratcher!

 

Anyone have experience upgrading gauges?
Per the instructions I’m curious what would be the ideal way to connect the wires for the gauge.

Ground-that’s easy.
Clock power- what should I generally use to power it, direct connect to battery or splice into something else?
Backlight- similar question but I can probably use the light bulb originally for the tachometer, it’s showing 11 volts at the connector.

The big question:
Switch key- Do I splice this into the wires of the key ignition and should I do it on the key ignition side or the engine side of the connector?

 

1982 XJ750 seca atari delete.

The Maxim wiring is a bit different, but this thread covers that.

Maxim gauges instead of Seca's? I have the answer for you!

 

I’m making progress!
Question about what a wire does...
The speedometer didn’t work when I picked up this bike so I’m not fully aware of its functions.
I marked this plug as “Speedo” and I was pretty much guessing the function of the colors.
There’s only power when the key is turned on.
Black is the Ground.
Blue has 11 volts to it.
White/Green has 7 volts.

What does White/ Green do??


Game plan:
I can probably use the Blue to provide power to the Gauge since it’s dependent on the key, Backlight can come from the Tachometer light bulb, and Clock Power CANT be dependent on the key so I may have to splice that into the battery side of the connector for the key ignition wires. (They’re always live)
So what about this White/Green wire???

 

white green goes to speedo reed sensor for the cancelling unit

runs between cancelling unit and speedo

 

Newb question, what is the cancelling unit and what purpose does it have, can I just cap it off?
I have the speed cable converter to digital that feeds directly to the gauge so I’m guessing the cancelling unit isn’t needed if there is no reed...

 

the cancelling unit turns off the blinkers after time or distance . it is not needed.
the blue wire runs the always on lights