First Cafe Racer Mod! 1983 XJ750 Maxim

Oil drain plug is leaking.... I installed a brand new aluminum crush washer that was a good fit, am I suppose to use something else? The one I took off the bolt looked odd, figured it was extremely smashed up from reusing too much.

What type of oil drain plug crush washer am I suppose to be using.

Current leaking Aluminum washer :
OD: 21mm
ID: 14mm
thickness: 1.7mm

 

aluminum or copper work. did you torque the drain plug.
the oem crush washers firt tight on id to the bolt

 

put some rtv goo stuff on the threads

 

No! Just use a very small straight-blade screwdriver and come in from the front of the connector (not where the wires come out of the back of the shell) and press/pry the little brass "finger" on the terminal "down" (towards the terminal flat spade)......that "finger" catches and latches onto a little recess inside the connector shell and thus locks the terminal in place. Sometimes it really helps if you push on the wire from behind the terminal you are trying to release....i.e push the wire straight into the shell, like you were trying to push the whole terminal and wire straight out of the front of the shell. This will release the tension on that "finger" and make it easier to push the finger "down" and thus release the terminal from the shell.

 

What 550H says is exactly right, but there is one other thing to know: one some models......and, perhaps, on different build dates of even a single model bike.......the factory did the "split" on that main brown wire (coming from the ignition switch) in one of two ways:

a) they "split" that wire (back up inside the taped harness) into 3 brown wires, and one wire is a thicker gauge than the others . This thicker brown wire is either used for the 20A circuit (which varies by bike; see the list below), OR, if all of the accessory circuits are 10A, then it really doesn't matter which circuit the thicker brown wire powers. The REASON that one wire is thicker is because the brown wire coming from the ignition switch is a thick wire (16-gauge), and the way that Yamaha did the "split" of that one main wire into 3 separate wire was to cut off a small section of insulation from this "mainline" wire, and then twist 2 more brown wires into this "stripped section" of the mainline thick brown wire.......in other words, the main brown wire isn't cut where the wires branch off, it's a full run from the key switch all the way to it's final resting place. A small section of insulation is stripped off of this main wire.......about 6" or so "into" the main harness from the point that all 3 fusebox wires exit the harness....and the two additional branch wires are sort-of "grafted" onto this bare section of wire on the "mainline" brown wire.

b) Of course, that's confusing to the end user, since he sees 3 brown wires exiting the main harness going to the fusebox....which one goes where?........so on most bikes, instead of mashing the two additional smaller-gauge brown wires onto the main brown wire, they did things the correct way........grafting two color-coded wires (red with white tracer and a red with yellow tracer wire) onto that thicker "mainline" brown wire from the key switch. These harness still features the thick brown wire (which is the actual wire from the key switch) as well as the appropriate color-coded wires for the other two circuits. In this manner, there is a 1-to-1 correspondence in wire colors on the input and the output "sides" of the fusebox, which makes non-experienced users more comfortable with the set-up, at least visually (and, it's the logical way to do things). In reality, it makes no difference; on the input side of the fusebox, all 3 accessory circuit wires......no matter if they are all the same color or are 3 different colors.........carry the same current flow from the key switch.

Notice the thicker brown wire must go to the accessory circuit that is 20A on the bikes down below; on other models, it makes no difference (functionally), but visually, you want the thicker brown wire to be directly opposed to the brown wire on the "output" side of the fusebox:

HCP393 Aftermarket fusebox 6-CIRCUIT ID DECAL, with labeling for 20A main fuse and 10A headlight, ignition, and signal circuits, for all XJ550, all XJ650, and 1983 XJ750 Maxim and XJ750 Midnight Maxim models.
$

HCP20241 Aftermarket fusebox 6-CIRCUIT ID DECAL, with labeling for 30A main fuse, 20A headlight circuit, and 10A ignition and signal circuits, for all 1984-85 FJ600 models.
$

HCP7152 Aftermarket fusebox 6-CIRCUIT ID DECAL, with labeling for 30A main fuse and 10A headlight, ignition, and signal circuits, for all XJ750 Seca, 1982 XJ750 Maxim, and XJ900RK, RL, N/FN, and F models.
$

HCP26951 Aftermarket fusebox 6-CIRCUIT ID DECAL, with labeling for 30A main fuse, 10A headlight circuit, 20A signal circuit, and 10A ignition circuit. For all 1978-79 XS1100 models.
$

HCP13475 Aftermarket fusebox 6-CIRCUIT ID DECAL, with labeling for 10A taillight fuse, 10A headlight circuit, 20A signal circuit, and 10A ignition circuit. For all XJ1100 and 1980-81 XS1100 models in the stock configuration (with the main fuse circuit remaining external to the fusebox).
$


If I recall correctly, it's only the XJ750 Seca/Euro models, and the 1978-79 XS1100 models, that use the "3 brown wires" on the input side of the fusebox; all of the others should have 3 distinct colors for the fusebox input, corresponding to the fusebox output side wire colors.

 

I thought I had it pretty snug but I guess this new washer had more “crush” to it than I’m used to! Use a Torque wrench and it appears to have stopped so far!

 

Update!

so I did trim back about 1’ - 1 1/2’ feet of wire (a lot more than in the photo), unwrapped most of it, untangled them since the were horrendously wrapped and tangled with little sense to them aside to just get to where they need to go, redirected a few of them for better allocation.

Added sequential turn signals in the front, other options didn’t work

upgraded fuse box

wrapped everything up with high heat insulating electrical toe and for some of the exposed wiring I wrapped in “Alex wrap” to protect and give them a clean look!

Now I’m getting a proper petcock from Len since my amazon purchase years ago is no where close to a logical proper fit!

then I can finally tune it!

Afterwards chop off that tail end, weld a hoop, and build a new seat!

 

What did you use for your front brake setup? Specifically referring to the lines and master cylinder.

I have my front end to work on soon and have the OEM 750 Seca brake union. Looking to use a MC on the handlebars down to the union then to each caliper.

 

I tried using those exact same brackets for headlight but they were way too long for my bike.

 

I got it off Amazon, at first it looked funky sticking off the bars but after converting to the Acewell gauge, I had an open mount so I just moved the master cylinder bracket over to keep it symmetrical, it’s different but I think it ended up looking great!
Previously I had a rectangular master cylinder lever setup but the downward angle of the cafe bars could potentially cause braking issues AND I broke the clutch wire connectors...
Here’s the mounting comparison:


They’re not showing as available on Amazon anymore but I’m sure there’s plenty available, they did come with a few of those funky army green bolts and clutch adjusters, I swapped out with chrome bolts and nickel plated the clutch adjusters.

I ordered the brake lines from Galfer, I think it was eBay where they had our specific bikes, if you reach out to them they can customize them for you.
I should have went with a 45 degree angle on the top brake mount and not the 90 degree as I have.
The line from Banjo to Banjo centers is about 11.5 - 12 inches but with a better angle, 11 inches would have been slightly more perfect.


Ive recently seen some videos where they show you how to make your own stainless steel brake lines and honestly, it looks really easy!

 

Luckily with the larger bucket and flipping them they turned out looking pretty good on my set up!
I thought the same thing at first so I moved it as high as I could, now it sits in there nicely.

 

Do yourself a favor, get an Acewell gauge!
They also have an adapter to convert the speedometer cable to a digital display

 

I’m currently getting 12.2 volts at the headlight connector, does that sound about right?
Is it still worth redirecting the headlight wiring?
I’ve been searching the forum but I can’t find any details on that setup.

 

start it up and measure volts at the battery, then at the headlight. the difference is what you would gain.
kind of hard to tell with numbers, just make a temporary jumper and go from the battery to the light. leave the original wires in place and touch the jumper in there. notice any change?

 

13.62 at the battery, tender attached, engine off.
12.60 at the headlight, no load
11.30 at the headlight with load

with 14* wire from battery to headlight:
- No changes with Low Beam.
- Very minimal difference on High Beam, nowhere near enough to motivate me to make changes.

If I need more light, then add more lights!
Which has me thinking...

What has anyone done for auxiliary lights?
Fork mounted or LED Bars?
Something in this area...

 

Is that brake union OEM? It's super clean looking

Seems I need to send a message to Galfer when it's time for the lines. Their eBay kit does not make sense to me, looking to move to only 3 lines just as you have done

 

We have a kit using 2 x hi-output 3.5" round LED lights mounted on the ends of a custom-formed bracket that bolts into the threaded holes in the frame cross-brace (i.e. truly bolt-on). Comes with hardware, wiring, handlebar-mounted switch. Available with either "fog" light beam pattern (wide spread) or "driving" light beam pattern (long-distance pencil beam). Contact us for more details.......

Actually, with the differences in voltages that you noted, you'll significantly increase the light output from your factory headlight by direct-wiring and using a relay system (we have those, too!). You're losing close to 2VDC at the headlight due to wiring, connectors (any of them oxidized? and how about the frame and battery grounds), and the switch, and light output from incandescent bulbs is not a linear function, i.e. a 20% reduction in voltage does not equal a 20% reduction in light output, it's more like 40% reduction in light output! This is why a relay system is a great idea for any vehicle (many modern cars/bikes already use such a system). The stock wiring use 18-gauge wire for some of the headlight runs, and that's just way too small in reality.

P.S. combining a headlight relay system along with auxiliary lights will make you a force to be reckoned with out on the roads, day or night...........

 

Yes it is OEM, their posting is confusing and doesn’t come with that part. It was actually my first test of stripping paint, learned a lot on that tiny piece!

 

I think it would have made a huge difference if I was still using incandescent but not on the LED headlights, I had to keep touching the wire to the connector to see the change it was so slight.

can you send some pictures of those auxiliary lights?

 

Oh, okay, if you have an LED headlight, then a small voltage difference will have almost no effect.

I'll try and get pictures to you (via e-mail) later today or tomorrow.

 

On this subject I have bought from a major UK supplier, two new ignition switches and a fuse holder. The fuse holder was a direct replacement using glass fuses. It looked fine, untill I looked at the crimped leads - they were tiny compared to the Yamaha ones. This made me look into the ignition switches - similarly, the red and browns were no bigger than the blues. Absolute chinese rubbish. I binned the fuse holder, and after checking the internals of the switches soldered the old leads onto the new switches. Fingers crossed and lesson learnt.
Edit to add a question to @chacal - are the light switch wires in the main/dip switch the same for bikes with and without headlight relay? Ie can they be swapped between bikes?

 

I purchased a marine grade fuse block, the upgrade was easy and even easier once I unwrapped the wiring and untangled them, suddenly had more wire to work with!
@chacal also sells them

 

SUSPENSION!!!!
Ok so I was planning on doing a hoop and seat setup just about exactly like this:


But upon setting up my phone to record and bouncing up and down on my frame in a way that I’m glad no one was watching... my tire goes up past the frames.
I planned on creating a flat pan that smooths out the underside of the subframe underneath the frame rails and down to the swing arm mounts but suspension compression would bottom out, possibly even solo!....

now my stock suspension is likely worn out, I had it to near max stiffness and it was still a concern.

What have people done with suspension to prevent bottoming out?!

I would like to occasionally have a passenger but if I have to make it a solo bike, I will.

Im 6’1” 195 lbs

 

You need higher rate rear springs.
When you say you had the rear suspension near maximum stiffness I take that to mean you had it at max preload?
Learn to measure "sag" both without and with rider.
Cheers, 50gary

 

rear wheel travel is 3.8 inches 96 mm. I guess you flatened the seatpad/lowered the seat.

do you have original rear shocks with the thumb wheel adjuster?

 

Yea they look original!


I’m curious that since the plastic dome under the subframe goes up about 2.5 above the lowest part of the rear subframe, should I increase the length of the new shocks by that much?
Being stock as well as 36 years old, I’m sure they were never quality in the first place since that’s where companies tend to go a little cheap on

I plan on having this welded on


And since I plan on having the seat thickness just a bit higher than the gas tank end, the passenger is going to need all that space for cushion!

under the frame rails I will be creating a mud guard, can likely give it a slight dome curve but very little

 

no that will affect the driveshaft angle and may wear out the ujoint quickly

thats a stock shock

maybe find a way to raise seat and cover the gap.

 

With bike on center stand, end to end of mounts is 14”, when I sat at it with max preload, it was 13”, when I hop up and down on it it moves roughly 3-4”... and that would be a very uncomfortable ride!

 

I do feel like I will have to curve the future mud guard underneath to have the space but I’m curious what others have used that have done similar projects

 

How about a 1 inch increase in shock length?

 

lot to be said for monoshocks

 

an inch seems to be acceptable

 

No load (center stand) 14” - with highest preload setting
Max compression 11” - lowest preload setting

bottoms out at top of frame rail at 11.5”.
So instead of putting a mud guard on bottom of rails, it’ll have to be above the rails just under future seat pan. Sounds like an extra inch on new rear shocks may solve clearance issues!
I’m surprised suspension only travels 3 inches!

(Those are the ladies finger nails)

So I can likely accept a shock between 380-390 mm with a max compression down to 290 Mm

I’ve seen Progressive, Hagon, and YSS recommended within a good price range in the forums, any other recommendations?

 

It really depends on your budget, but from personal research I came to conclusion that Progressive is best bang for the buck when it comes to quality.

 

What you are calling the dome or bulge, (the plastic, black curved thing) is called the inner fender. There is no way you should have to change or modify the inner fender for tire clearance.
The top of the inner fender will be at the same height as the cafe seat so no contact will happen even at full compression.
The cafe type "hoop" might contact the tire on full compression if the "legs" of the hoop are too short allowing tire to contact the hoop. You're good with adding photos, show a mock-up of the
hoop in place (tape it in place where it would be welded) picture in pure profile and you'll be able to see if the tire will hit the hoop. If the tire contacts the hoop you may need a hoop with longer legs
(legs being the straight part of the hoop) All things being normal the suspension should be able to move though it's full range of motion without hitting anything.

"when I hop up and down on it it moves roughly 3-4”... and that would be a very uncomfortable ride!" Not to be rude but no, not necessarily. What would make a rough ride would be a suspension
that's too stiff, non-compliant. All the shock of the bumps would be delivered to you and your lady friend's backsides. Also the "thickness" of the seat will not make a difference, the placement of the
underside of the seat. (seat pan) could cause tire to seat contact. I'm doing something quite similar, I'm keeping the factory inner fender and extending it straight rearward (horizontally) even with stock shocks there's
no interference or contact. I'm using 13" Center to center YFR (cheap chinese) shocks but with the 8mm (heavier) diameter coil spring wire. The softer version of these shocks have 7mm wire.
Sorry for the long post just trying to clarify some points.
Cheers, 50gary

 

I was thinking the same thing

 

[QUOTE="when I hop up and down on it it moves roughly 3-4”... and that would be a very uncomfortable ride!"[/QUOTE] @50gary
No worries, I meant that I had it set to max preload settings to test the limits of it all, so the settings would have been the uncomfortable part vs having it where I normally would.
When I used the ratcheting tie downs to hold it for measurements and for testing, the tire went just above the top of the frame rail "legs" which is actually about where I planned on having the hoop...
You make some great points and I may have to consider whether to make it solo and fabricate a rear tire fender or go longer for clearance of the hoop.
Ultimately I wanted the entire rear inner fender space from top of rails to be seat cushion.
Not wanting the setup to sit so high and thick as the stock seats were.

 

@50gary So when looking through your project, you basically did what I intend to do but you have to upswept hoop yet created the rear fender which would technically give you even less clearance.
This works for you using a shorter shock with heavy duty springs? have you bottomed out ever?

 

you should get a stick with holes the distance of your bottomed shocks and use that for shocks in your eye balling adventures
quit bouncing the bike, your going to hurt yourself

 

I really liked the Progressive 430’s but they have a cruiser look to them (great for Bobber style) so I’m going with the 412’s 13.5” and here’s why!

After conservatively chopping off unneeded metal and measuring clearance with tape, total suspension travel unloaded vs loaded with 2-up “simulating bumps” was 2.75”.

me sitting solo, all 195lbs.


simply 2-up without moving, the tire reached the bottom tape, bottoming out.



the rear tire would reach the upper tape on the frame rail but not quite hitting it but easily broke through the bottom tape.

so my conclusion is that the stock 12.5” worn out 36 year old shocks should be fine getting replaced by Progressive’s 412’s 13.5” shocks that will give me extra space for compression yet resist bottoming out much better, if not, it’s Amazon and I’ll just return them!

 

Bike is acting weird.
I started it up and let it for a few minutes and then shut it off with the key.
Came back 30 minutes later to turn it on so I can start some synchronizing and all I heard was a click...

Battery has been on a tender and well maintained.

Fuses are good.

Gauge acts unusual sometimes when turning the key on, sometimes it lights up, sometimes it doesn’t, also headlight acts a little weird with flickering and sometimes not coming on, oil light only shows when I have the kill switch set to off, nothing happens when I push START, sometimes I get a click near the battery area but can’t find it since it’s a bit random.

I suspect the Rectifier, how do I test it?


Should I be looking at something else?

a 650 diagram appears more accurate than my 750 wiring diagram

 

Sounds like a fusebox issue

 

Checked the fuses and they’re good, none of them popped, and it ran for about 3 minutes straight, turned it off since it starting gradually revving higher and higher as it warmed up even though I tried to turn down the idle speed.

I can change the fuses just to be 100% sure, they’re cheap and it’ll rule out the possibility of funky fuses.

I was going to do the carb tune and colortune today....

 

jump the solenoid

 

Hope I did it right, hard to see how people were doing it on YouTube, it didn’t click it do anything so that means it’s busted?

 

the two big bolts on the solenoid, stick a quarter between them
like this
https://drive.google.com/file/d/0B4j6bf_0WGweZW5MbWpCRFRYeWc/view?usp=sharing

 

@Polock Oh! That’s so much easier than how people explain it on YouTube! I did it with a screwdriver and there was just a click...
So that tells me the solenoid is dead!!

I also tried to bypass the solenoid, hopefully I got this right by connecting the battery positive to the only bolt on the starter using a jumper cable, still only got a click from one of the diode boxes.


I heard the “Boing” of a spring within the solenoid.
Also noticed a very faint sound from the coils like they were charging up “weeeeeep”, it was hard to notice even though I have really good hearing.

 

that says your starter is broke
put it all back together and start from the beginning, charge the battery and right now think about the starter

 

So I was right when I turned the key on and connected the battery positive terminal to the starter it should have kicked over?
I’m gonna pull the starter and see it it works when removed

 

Ugh! I tore the starter part and everything met spec per Chacals posting on XJ4Ever but it still won’t work even check for bolt wiring to make sure it wasn’t touching the body and shorting out.

If anyone is bored, regreasing the starter gears is probably a good idea, they were sticky and didn’t run as smooth as they could be!

Looks like I’m putting in another order with @chacal