NEW XJ750 Owner With Some Quesions Please

hello all

i just got my hands on a 1981 sec750 in good shape, i am ordering a haynes manual for it from ebay. but in the mean time i have some questions to get me started in fixing it up.

1. the warning light displays, oil, brakes and battery, i have checked the oil with the bike upright and the glass is full. both brakes are strong and my battery holds 12-12.5 and when the bikes running goes up to 14. so seems to be charging fine. is it it possible the warning sensors are pooched? if so what should be my next step?

2. my bike fires back a bit when i let go off throttle, i noticeded the header bolts are loose. would this cause the fire back. or is it strictly the carbs are running lean?

3. does this bike not have brake fluid reservoir?

any help is greatly appreciated thank you!

 

Sounds like maybe there is a bad connection somewhere, or bad ground probably having to do with the warning light module. These bikes are old and the connections get flaky. I would consider pulling every connector that you can get to and inspect and/or clean it and put it back together with some silicone grease.

Also check the main ground wire from the battery to the frame and engine block.

 

The battery sensor is mostlikely gone.
chacal has a bypass kit for that.
The brake sensor is in the reservoir. It is mounted behind the headlight.
The oil level sensor is located in the oil pan. You will have to trace the wire from that point up to the headlight to see if there is a bad connection.

So while your at it:
Check date codes on rubber brake lines.
check date codes on tires
Check rear brake shoes for delamination
if any of those are out of date or coming apart you should work them into your budget to get replaced.

MN

 

The battery sensor measures the fluid level not your voltage.

 

The battery sensor does measure voltage in the cell that it is located in. chacal has come up with a battery sensor by-pass kit that eleminates the battery "wet" sensor and makes the computer think that is taking the voltage measurement in cell of the battery.
The kit turns the battery warning light into a signal that actully means that your alternator is not charging vs the cell in the battery is low on water. I make a point to check the water levels more often.

MN

 

so if the battery levels are low then it needs to be filled with distilled water am i correct?

 

Yes.

And yes you have a brake fluid reservoir; it's "remote" like your cable-op master cylinder and hidden inside the front shrouds somewhere.