Click on the Banner to Visit the TX/XS500 Forum

March bom

Saturday, November 27, 2010

25 Micron Oil filter

The OEM oil filters have long been out of production,the Emgo replacements have a tendency to leak,and filter prices aren't getting any cheaper.On occasion you can locate a factory oil filter adapter kit.I decided long ago to come up with my own system.It makes for 10 minute oil changes too! It uses an industrial stainless steel 25 micron filter.Flowezy part # Y2-SS-1/4-25-F3 [] Jim

Thursday, October 28, 2010

Ignition Improvements Part 2

Nippendenso also makes decent points sets.If you want to run hot coils there are many 3 ohm choices: Dyna is always good stuff, and auto coils are abundant.I use Pertronix epoxy part number #40611 and NO ballast required.I purchased mine from Summit Racing. Now you need some good plug wires.Dyna universal set#516? work great and use the nipple on the end of the plug which is much better then just the threads.My favorite choice of plugs would be the NGK Iridium DR8EIX[stock heat range].These are expensive at about $10/$11 each.Now if you are a throttle twisting freak you can add the Dyna DRL300 revlimiter and it is adjustable to whatever RPM you want to set it at.I rev mine to 9500 with my tune up.I bought all my Dyna stuff from Pingel Enterprise, but shop around! Also make sure your mechanical advance has good springs and moves freely.Take it apart, clean it and lube with motor oil or light grease.You should be able to use the springs for the XS650 from MikesXS. Good Day! Jim P.

Ignition Improvements

Improving the igniton can be grouped in two ways:using points or going pointless.Pointless the best option is the Newtronics kit # YAM3.It is out of production,but I am sure their are some sitting on a shelf somewhere.Newtronics was bought out several years ago and if we show a big enough demand we could probably influence them to build more kits.I have tried contacting them,but so far no response.They are located in England.I have used this kit and it works great.You can always modify an existing kit for another bike or build your own from scratch if your are up to the challenge.Using points really isn't all that bad.You can find FactoryYamaha points sets and tune up kits by visiting older Yamaha shops[especially if they have been in one location for a couple of decades], or of course there is always Ebay[just saw a complete OEM kit go for $10 which included points,condensor and 2 plugs!]. You can get good Hitachi tune up kits or individual points sets from Sudco International in California.While checking them out,you may want to order parts for you stock CV carbs! Yup, they have some of that too.Now that you have a good set of points adjusted properly with a touch of oil on the felt pads you can add a Dyna Ignition amplifier DBR-2 which drastically improves performance and points life.

Oil filter adapter kit

Right now on Ebay Germany is the very rare adapter kit to convert the oil filter to a common filter.First time I have ever seen one actually available. 60.00 Euro. I would jump on it but I use something I built .10/28/2010 Jim

Monday, October 25, 2010

Brakes Broke

Both brake calipers were seized up. That's not uncommon on bikes that have sat for a long period of time. Most times, you can rebuild them after carefully stripping them down. This is the case with the front caliper, not so the rear.
Rebuilding the calipers is a pretty simple and strait forward affair. As long as the piston and bore are in good shape,you just need to replace the seal and boots.As you can see from these pictures, the rear bore and piston are trashed and can't be saved. So it is to Ebay I go to find a suitable replacement.There are several candidates as the XS model calipers are interchangeable between models. The front is differentiated from the rear with bleeder screw placement. So if your looking to replace the rear caliper, make sure you check the bleeder screw location before pulling the trigger on a used one.That is about the only difference I can find between the two.

Till Next Time..............

Monday, October 18, 2010


The prevailing theme with this bike is rust. Rust is the biggest battle I will be fighting in straightening this ride out. As one would expect, the exhaust was not immune to the ravages of corrosion. In the interest of keeping cost down, I will be using the original head pipes although the mufflers are just too far gone to save.

The joint nut would not budge, so had to crack out the old cut off tool and buzz the muffler off. You want to cut about two inches down from the nut on the muffler so not to cut into the head pipe.
Once the head pipe and muffler are divorced, it's time to turn your attention to the joint nut. You will want to take your time cutting the joint nut, to keep the head pipe intact. Once all all the cutting is done you can use a chisel or a large standard head screwdriver to pry the nut off.
And there you have it, you're now free to run 'em strait or slap on the mufflers of you choice.

Till Next Time..............

Saturday, October 2, 2010

500E off to a good start

After rebuilding the carbs, fresh plugs, new oil and sorting out the wiring, the ol' XS is purring like the proverbial kitten. this bike is in such a bad state of repair, I thought it would be an exercise in frustration getting her up and running. The previous owner stated that it ran great when he parked it three or four years ago. How many times have you heard that statement. I still have a long way to go, but I am off to a good start.

Wednesday, August 18, 2010


The carbs on the ‘78 XS500 are very similar to the ‘80-‘84 XS650 34mm Mikunis. There are some subtle differences, but you can rebuild them using the ‘80-‘84 XS650 34mm parts. I had to modify the float bowl gaskets slightly to accommodate the older 34s. All the main jets and pilot jets are interchangeable. The needle valve seat is different so you can use the seat you have if it isn’t wore out. Mine was fine so I just swapped out the needle valve.
The slide diaphragms were shot and being a cheap bastard I did not want to pop for the whole assembly. They sell at MikesXS for sixty-nine bucks a piece. There is a guy that sells replacement diaphragms on ebay for $49.00 plus $10.00 shipping. You have to wait for the auction to end which may drive the price up considerably. I opted to go with JBM’s products. He resurrected a old rubber press and makes diaphragms for a few different sizes of Mikuni carbs. The 34mm of the XS500 and the ‘80-‘84 XS650 have the same 73mm diameter and they fit my carbs like a nice pair of leather gloves. As far as I can tell, JBM is the best choice by far, a quality part for a great price. Only $39.00 for a pair and just $3.00 shipping on top of that. They are a snap to insatall and they have easy to follow instructions on their site. I highly recommend them.

I’m not going to be running stock filters and exhaust, so I bumped up the main(132.5) and pilot (42.5) jets to 140 and 42.5 respectively . Plus I bought one size up from there145, and 47.5 just to be on the safe side if the bike doesn’t run well with this set up. Just a note, When buying from MikesXS, have your total order ready when you purchase. If you forget something they charge you $7.00 shipping on all orders even if the part your buying is only a buck. If you do forget a part, if you get the order on the new one before the first order ships, they will add it to the first order at no additional cost. It would be nice if they had a phone number in addition to the checkout, just saying.

The total for rebuilding the carbs including the extra jets comes to $105.95

float bowl gaskets $4.00 X2 $8.00
132.5 main jet pr. $6.00 $6.00
140.0 main $6.00 $6.00
145.0 main jet pr. $6.00 $6.00
42.5 pilot jet pr. $6.00 $6.00
47.5 pilot jet pr. $6.00 $6.00
Float Valve $9.00 X2 $18.00
Shipping $7.95

slide diaphragms Pair $39.00
Shipping $ 3.00

Total $105.95

After getting the carbs sorted out and mounting them on the bike there seems to be electrical issues as well. I ordered a new fuse block from Mikes ($24.00 plus shipping) and have to diagnose why else she is not putting out any fire. So it will take awhile for me to track down the electrical problems as this is where I shine the least. I will lean on J.J. and see if he can make any sense of it. It’s not too bad so far I’m only into it for just over a saw buck.

Till Next Time................................

Saturday, August 14, 2010

Looking For TX/XS 500 Resources

There is not a whole lot of info out there about the Yamaha TX/XS500 models. It is my hope people with info will send it here so we can have a place we can tap for information on these bikes. Also, you can send in pics and and details of your TX/XS.
I have listed in the links all the sites I could find with info on these bikes and will continue to add links as I find them. So if you have one of these bikes, don't be shy, share your story here.
Yamaha TX 500
Air cooled, four stole, two cylinder. DOHC
398 Bore x Stroke 73 х 59.6 mm Compression Ratio 9:1
2x 38mm Mikuni
Ignition / Starting
Battery and coil /
Max Power
48 hp @ 8500 rpm
Max Torque
4.5 kg-m @ 6500 rpm
Transmission / Drive
5 Speed / chain Frame Full cradle frame - Duplex type" and is 100% of circular steel pipes!
Front Suspension
Telescopic fork.
Rear Suspension
Dual shocks swing arm, preload adjustable!
Front Brakes
Single 10.5in dDisc
Rear Brakes
Front Tire
Rear Tire
3.50-18 Seat Height 32 in
458 lb
Fuel Capacity
3 4 gal

Model: Yamaha XS 500
Displacement: 30.45 cubic inches)
Engine type: Twin
Power: 49.00 HP @ 8250 RPM
Compression: 8.5:1
Bore x Stroke: 73.0 x 59.6 mm (2.9 x 2.3 inches)
Valves per cylinder: 4
Fuel control: DOHC
Cooling system: Air
Gearbox: 5-speed
Transmission type
final drive: Chain
Weight wet 463.0 pounds)
Front tire dimensions: 3.25-19 Rear tire dimensions: 4.00-18
Front brakes: Single disc Rear brakes: Single disc Top speed: 73.3 mph
Fuel capacity: 3.96 gallons