Slightly altered 83 XJ750 Maxim

Have a question for someone that knows more about XJs than I do.

I just checked logs from today’s ride and it shows my max RPM were 12,873?

Is this even possible?
Tach seems to function fine and RPM matches speed at least when I look at it. But such high RPM kind of throws me off. I didn’t even know these engines could spin that fast.

 

this says it's possible
http://thefirstgensite.com/code/maxrpm.htm
i think it voids your warranty though
750 stroke 2.22 inches

 

Received new gas cap today, but I didn’t want to use two keys (1 for ignition & one for gas) so I ended up taking parts out of new cap and swapped them over to my original cap. New seal, new springs, new locking mechanism. Greased everything inside and it seems to operate very smooth. Will have to do some testing to see if this fixed my problem with spilling fuel, but so far after tipping bike to the side until foot pegs touch the ground there are no leaks.

 

I cave in and ordered new rear wheel and new tire. Should be here in a week or so.

 

Rust-oleum played a joke on me today....

I decided to paint back side of my frame to prevent it from rusting until frame goes in for powdercoating later this year. Stripped the bike, masked everything off, degreased the frame and started spraying, everything went smooth, no runs, no dust. Waited around 8 hours for paint to harden and then slowly started putting bike together. The way I modified my bike, parts have to go back in exact order, otherwise nothing can be fitted since “tolerances” are quite tight. Once I was half way done, I mounted rear wheel & brakes and said WTF out loud! At that point sun started making its way into garage and I realized that what was supposed to be BLACK paint, was actually the darkest GREEN I ever seen!

Let’s just say I was beyond pissed!

Stripped bike back down, masked it all off again, degreased it once again and proceeded to paint with different satin black paint.
Now it came out exactly how I wanted it. Left it as is and will be putting it back together tomorrow.

I’ll include a few pictures.

 

Spent last couple of days working on my XJ. Back half of the frame & rear brake plate received paint (temporary until it all goes into powdercoating) and did paint correction on the gas tank.

New rear wheel and tire should be coming in sometime next week.

 

The few race bikes that were built ran the redline at 12k.
The rules about what's safe change a bit when prestige is on the line instead of warranty claims.

 

Went on the longest ride so far, 155 miles. Bikes performed well, but today was first hot day riding and I will be going up in jet size. Bike runs a bit lean.
Besides that, I also rode through a full tank of fuel and was able to put 140 miles on it before having to switch to reserve, good range imo considering that tank is a lot smaller than stock. Also, achieved a milestone of 500 miles on the bike in its current form.

 

that's a seca 550 tank correct?
4.2 gal total 0.9 reserve

so about 42 mpg not bad.

 

Correct on the tank model. My tank sits at slightly different angle than it does on XJ550. So I willed up I think around 3.7-3.8 gallons. Calculated 38MPG.

 

and I'm thinking you do not ride conservatively

 

Lol
Not at all! That’s another reason i sold 1000CC sport bike and bought old XJ. It’s plenty of fun to ride and keep it at somewhat reasonable speed. I am not responsible enough to own fast bikes. Haha

 

Received new rear wheel and tire today. Will be dismounting old tire that new wheel came with and painting new wheel tomorrow.

 

Love the look of your bike so far. The rattle can green is the same colour as an IKEA couch I have and my son swears up and down it's black.

 

View attachment 35132 New rear wheel and tire mounted. Didn’t make as much of a difference as I expected but still an improvement.

 

Ties the front and rear togeather nice looks like it was ment to be.

 

Swapped in new jets yesterday since I felt like it was a hair too lean and went for a ride today. Well, I think I went too rich as for the first time in it’s life bike started bogging on low throttle. Needless to say, I will be going back to what I previously had.

 

Update.
Spent most of Saturday messing with carbs, swapped Jett’s, synced them and now bike performs flawlessly! Super steady idle at 1k rpm, zero bogging, great throttle response, no popping on deceleration, drops down to idle from redline instantly, exhaust sounds smooth and deeper.

Also, this morning went to Sears point raceway to get my suspension adjusted and fine tuned. What a difference that made! Bike is very smooth on imperfect roads, absorbs impacts mid corner without getting upset. I would highly such tuning service to anyone with adjustable suspension!

 

Out of curiosity, what jet combo did you end up with?

 

43/134