yamaha xj650 help

Hey everyone. I just got my first bike last week. 1981 yamaha xj650 maxim. Im 17, so obviously im on a buget. I need to replace the orings inside my petcock, and i need a new front break rotor. Any good places to order from? I cant find the size for the petcock ring. I dont want to buy a full rebuild kit because of the cost. Im also looking to drop thebike a few inches in the back.any ideas how to do this cheap? Im also going to repaint it. Sand,prime,paint,clear coat, with walmart spray paint? Im doing the tank, & know any spilt gas will eat the paint and make it run. Any alternate ideas?
Also looking for new-
Bars (probably cheap drags?)
Grips
Airfilters. Good websites i can trust to order from? Ive been looking at stuff on eBay, but id perfer toorder from a motorcycle site soi know exactly what im getting.
im changing the oil + filter&spark plugs. What else should ido to just clean it up & make it run a bit better?
Im going to cleanthe carbs. Anything else i should clean?
Also,my speedo/tach make a loud whirring noise when the needles move. Im assuming the need to be cleaned?
Thanks for your time & any imput you have!

 

Top right hand picture on the page for ordering. XJ4Ever PM Chacal hes got just about everything

 

thats wierd im 17 and just bought an 81 xj650 maxim about 2 months ago

look at bikemaster i got drag bars for 25$

i ride bmx so i just put some bmx grips on

and i bought some airfilters on ebay for 40$, there no k&n but they should do the job, just type in 51mm cone filter on ebay and you should be able to find some cheap ones

 

Haha thats crazy, i bmx too. When you put the bars on did you hvae to reroute the cables? Or replace any? are you sure i need a 51mm air filter?i read online that i would need a 32mm cone..

 

Ha i bmx too. Vintage only though.

I grabbed my drag bars from emgo at motorcycle superstore. I think they were like 12 bucks. I grabbed a set of metal malusha dirty bike grips for 6 bucks at the same time. The dirt bike grips go well with the bike since they have little skulls on them and are fairly soft. Ive had no end of cable issues but i had the higher stock bars. The only cable ive been able to reuse is the throttle and its kinda iffy.

Pod filters may sound nice but they are a tuning nightmare. Very hard to get to run like oem. Also unles you pull the motor your gonna have to cut up your oem box to get it out so theres no going back.

 

The diameter of the inlet to the carbs is 51mm. so 51 mm pod filters, or cone filters, will be what you would search for...IF you are willing to put the effort into tuning for pod filters. From personal experience I can say its worth it, but I did spend close to 12 hours one day getting the right jets, and tuning adjustments... and you cant do any of that right until you check the valve clearances because if you have to change out any shims you will have to start tuning all over again.

All of this is necessary because pods allow more airflow (as would doing straight pipes or removing the cone mufflers). With more airflow the mixture of fuel and air in the engine would change creating a "lean" mixture (too much air per unit of fuel). A lean mixture will burn hot. VERY HOT!!! It will melt parts in the engine any can in some cases weld the engine up solid. I was in a car that did that once; it was scary as hell and I cant even imagine what would happen on a motorcycle if that happened.

LONG STORY SHORT- do not get pods if you are not going to tune it. you will ruin your new bike. If you are going to tune it... it will be awesome

 

yea ill need to re route and get some new ones. and im up for the challenge of pods

as for cutting the airbox out i got mine out with only one small crack down the side whiich im sure could be repaired

 

I'm Impressed. yeah if you get a low power soldering iron you can melt the crack shut... or some plastic epoxy.

 

Worry about rebuilding the BRAKES before you worry about trying to set the carbs up for pods. Experimenting with jetting can get expensive fast.

For your first bike, I'd go for SAFE and RELIABLE so you can LEARN TO RIDE before you go cutting up your airbox and the like.

You need to be spending your money on brake pads and shoes, brake caliper and master cylinder rebuild kits, brake LINES, and the parts you need to get the carbs working correctly in stock configuration.

Unless of course, you don't plan to actually ride the bike.

 

Wow, what a similar situation. I was 17 when I got my first, and current, bike - a black 1981 xj650 with 26,000 miles in less than stellar condition. I'm almost 24 now and after a good amount of work, a good amount of money, and A LOT of learning i've come a long way. This website and the people who frequent it are invaluable! The only time i've used a mechanic was to have a new front tire placed on the rim, which i'm about to have done again, and to have old wheel bearings popped out of the hub, which was done free of charge. Awesome way to both learn and save money. Bike looks and runs well and hopefully will continue to serve me a good while longer.

I've used Ebay a great deal, but understand wanting to use a dependable place which provides good service with new parts. I have used bikebandit.com a lot, as well as a few other online shops here and there, and have found bikebandit to be a good source. I used XJ4Ever a couple times more recently I believe, and have no complaints.

Good luck and enjoy the experience!

 

yea i just took out the rear engine mount bolt and it sagged maybe half an inch, maybe. but it helped, and you just cant be afraid to get a little rough with it

 

i have the really high stock bars too :/// they're really uncomfortable and ugly.
im really not good at tuning carbs. my brother is though, and said he'd be willing to assist me if i forgot a 50$ debt. so i migh go with that, and learn while i do it. i havent even looked at taking my air filter out... from what you guys are saying its hard to get it out without breaking it?
I think ill get new bars, & replace the brakes and everything at the same time so i can get the right size brake cables.
but yeah, my bike has 39k miles...

 

It's the air box that's hard to get out. You have to pull the engine out to do it right. Other than cutting it up there's not much of another way to do it. Then there's no going back. You won't just have to tune the carbs tho. Most likely you will have to change out the jets. I was one of very few who didn't have to make major mods to the carbs to make them run on pods. Most have to do a full rebuild with different jets.

 

yea its difficult to remove, you just need the carbs off the clutch cable braket off and i think thats it, aswell as taking out that rear mount so it sags a bit

ive also heard of people heating ti up with a heat gun or hairdryer so its plyable

btw the trick is it comes out of the right side of the bike, with alot of shimmying,

 

By no means am I trying to discourage you. I say do it up!!! I just want to make sure you're aware of the job this is going to be. It is worth it in the end though when you can hold your head high and say you got your pods to work. You will be part of a large group of people who chose pods. But a small group that did it right

 

If you intend to go with pods and play with jetting, get it running perfectly first.

If you start doing mods when a fault is present you WILL chase your tail.

 

So very true dark

 

Before you scrap the Airbox and install Pods ...

Get your Bike tuned-up to its maximum performance ---> Stock!
Get to know what its like to push the Start Button and have the Engine start right up.
Experience the joy of Idling at a light and getting out-of-the-hole without any hesitation.
Feel what it's like to be able to clutch, match-rev's with the tranny, ... then, wrist the Throttle wide-open and send the needle on the tach over toward the Red Line without feeling like you're running out of gas or dragging a fully-deployed parachute.

I don't think it is good business for anyone to recommend to a New Member that the New Member install Pods without first advising the New Member to be prepared for a MAJOR DISAPPOINTMENT after doing so!

Given all the discussion and consensus; the recommendation is tantamount to giving-out BAD ADVICE!

If there was a list of reasons for what causes people who buy an old, used XJ-Bike, the most trouble in getting the bike to deliver the "Tanoshimu" for which it is intended, ... here's what would probably be right smack-dab at the top of the list:

Pods.

 

For every one person that says pods are great there are at least two that will tell you that they regret ever detroying the original airbox to get it out. Because once you have destroyed the airbox. You are stuck with the tuning nightmare that you get with pods. Until you can locate another airbox, and get it installed without detroying it in the process.

If you want more power, and go faster. Get the bike running in top notch shape in stock condition first.

Before you get to far ahead of yourself getting in the go fast mode. Make sure you can STOP.
This will entail a complete overhaul of the brake system. Both front, and rear. New shoes, pads, and lines. Rebuilt master cylinder, and caliper.

Then progress onto the engine.
Check, and adjust valve clearances
Compression test to set a baseline condition of engine
Clean, and rebuild carbs
Bench sync, vacumm sync, colortune

The next step would be to make sure the electrical system is in good condition.
Replace the known faulty fuse block with an updated blade style fuse block if not already done.
Check the brushes in the starter, and generator. Replace if necessary.
Check,and clean all electrical connections in the wiring harness.
These things alone will cure a majority of the electrical problems you may come across.

By the time you have all of this in good shape. You will have a good reliable bike to ride.
Feel free to modify, and personalize the bike to make it truly yours knowing that you started from a good foundation.

Ghost

 

im not planning on riding the bike till next summer. my parents are both very much so against it, and i need their signature to get the license. so my plan was to rebuild & customize it this summer, then ride it next year. when im 18& no longer need their signature.
so after i over haul the brakes, put new bars on, repaint the tank & other various parts, & other basic matenance, ill probably try to make the switch over to pods. i'll have the whole summer to tune/jet the carbs.

 

Nothing new but I will second what is already said. I was planning on trying POD then after about 2 months of review the forums decided against it. With that said I saved the airbox rather than cutting it to shreds to take it out. So definitely just keep everything, you never know when you may change your mind.