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2001 Gas Gas TXT 321

Discussion in 'Trials' started by Grynch, Sep 14, 2019.

  1. flyinfuzz

    flyinfuzz 2 Quarts low

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    Agree on the rear air box about checking it closely . That and fork seals leaking were my biggest problem with mine . Other than it getting tired in a section and laying down to rest :muutt
    #21
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  2. Grynch

    Grynch Long timer

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    Thanks so much for the info, this bike was purchased by a guy named Hans who used to own Redwood city Honda who purchased it off John Moore from Santa Cruz.
    #22
  3. Grynch

    Grynch Long timer

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    After I filled the coolant system with 50/50 distilled water and vinegar, I warmed up the bike, then topped it off and put the cap upside down on the neck of the radiator. This is what happened over night.

    IMG_20190918_182339903_HDR.jpg IMG_20190918_182346044.jpg IMG_20190918_182356760.jpg
    Won't be using the vinegar mixture again to clean system.
    I put the garden hose gasket in the neck of radiator. It still leaked after getting warm..
    Also the lights worked when first started, now they do not. Is there a fuse box somewhere? Anyway, the bike runs real well otherwise.
    #23
  4. Hoss Cartright

    Hoss Cartright 219.474.6657

    Joined:
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    Oddometer:
    970
    Location:
    Galapagos Islands
    If you are filling to the top of the radiator, it will still "pee-off" the excess expanded coolant when it gets hot. Correct radiator fill height is when it is not visible in the neck of the radiator. When cold, when you hard-squeeze the long radiator hose (from water-pump to bottom of radiator) you should see the fluid rise into the very bottom of the top neck. So, perhaps your "still leaked" was due to the excess being pushed out during the expansion and contraction cycle.
    Even though the cap lower seal looks good in the first image in your group, if it continues to leak then obviously you need a new cap.

    When you heat-cycled the engine, your cooling fan started and ran. Correct?

    No, there is not a "fuse" - The lights are there for some Europe countries homogulation requirements but we found them to mostly be a nuisance and a common source of electrical problems. Especially in that poorly-made Leonelli handlebar multi-switch and its bulky harness and wad of plug-ins behind the light that interfere with the control cables and hoses when the bars are rotated left to right. In some crash scenarios, some of our customers fractured or smashed that somewhat fragile handlebar switch assembly and this internal damage to the housing grounded the kill button circuit which can be frustrating to diagnose the reason why the bike will then not re-start. Many a failed tech-inspection or DNF have originated in that switch...
    When working, the lights are: "to be seen" not "to see with".
    There were instances where the cables fouled with the backside of the headlamp and caused a "positive" spade connector on the back-side of the headlamp to rotate and touch the ground side of the headlamp bulb socket. This resulted in a direct to ground of the A/C circuit and subsequent melt-down of the D/C rectifier which provides the D/C power to the fan... So......... A short in the headlamp leads to engine and wiring loom overheating issues and fan motor related electrical component failures.
    All light related parts are on the yellow wire side of the system - Almost all USA users remove all of the lights and related wiring components and switch. Preferring to mount a standard kill-button as the requirements here for competition are for removal of headlamp for mounting of a front number plate, and of late, more and more trial clubs and the AMA/NATC are enforcing the lanyard "man-overboard" magnetic kill buttons.

    Wiring diagram for that bike
    Kok2001.jpg
    #24
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  5. Grynch

    Grynch Long timer

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    Fan does not work. I will try to look at it over the weekend, thanks again.
    #25
  6. Hoss Cartright

    Hoss Cartright 219.474.6657

    Joined:
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    Oddometer:
    970
    Location:
    Galapagos Islands
    Presuming that we have about 14V A/C on the yellow wire when engine is running, the first test is to "jump" the thermostat with simple jumper wire to bypass it, then with engine running, fan should run constantly. If fan does not run, during same test, check red wire going from the rectifier to the fan motor, it should be making about 12V D/C. If this is working, then check your fan motor with external D/C power supply.
    These systems are simple series circuits and are relatively easy to diagnose.
    This (including the lights) could be as simple as a connection unplugged in the yellow wire circuit.

    Your photo

    2001_TXT_under_the_hood_CU.jpg
    #26
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  7. Grynch

    Grynch Long timer

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    Thank you
    #27
  8. Grynch

    Grynch Long timer

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    Well I got back to the project. Since finding that the impeller inlet and outlet were completely clogged, I kept wondering if the cylinder and head were clogged up. I needed peace of my mind, so I ripped off the head this Sunday afternoon. Ah the memories! How nostalgic, brings back memories of being in Acapulco, Mexico back in 97' trying to put some rings in the 94' YZ 125 two days before a race in Mexico City .....Anyway , that is another story, for another time.

    Here are some photos:

    Had to take out the horn , then coil IMG_20191013_151552447.jpg IMG_20191013_152229487.jpg
    Slip radiator out through the left
    IMG_20191013_165534253.jpg
    Unscrew Allen head bolts opposite sides, going back and forth do not to warp the head.

    IMG_20191013_153516546.jpg
    Yeppers, she is looking like five hours ride time to me. I can still see the factory hone marks.
    IMG_20191013_153856507.jpg IMG_20191013_154334360.jpg
    The letter A is stamped on the Piston, which (edit) usually means stock bore. Cleaned up the top of the Piston and head. The arrow points to the exhaust for installation, so as not to put Piston in backwards. I might ad if doing the rings and you do not have a feeler gauge for ring end gap. My friend Criss Wortman, of CW racing engines, taught me to use a business card. Criss does all the porting and head work for Frank Nye of Engines only. IMG_20191013_154555238.jpg
    Cylinder has 98 stamped on outside, ven though it is a 2001 , probably means it was manufactured in 1998.
    IMG_20191013_162110099.jpg

    Here is where it might bite me in the butt.I used grease to hold the o- rings in place for the cylinder head. Hopefully this does not have adverse effects on o- rings. IMG_20191013_161621167.jpg
    Buttoned her up so not to be exposed to elements.

    Attached Files:

    #28
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  9. Grynch

    Grynch Long timer

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    Had some day light left, so I decided to use the SOS pad on surface rust. IMG_20191013_164929944.jpg
    IMG_20191013_164942469.jpg
    Not finished yet but it is a start. This is what other side looks like.
    IMG_20191013_164951959.jpg
    Spokes
    IMG_20191013_165832839.jpg
    Head pipe
    IMG_20191013_165541825.jpg
    Need to check Fan, thermostat, and lights next. Now, at least, I have peace of mind, in regards to the possibility of corrosion in the the cylinder and head.

    Attached Files:

    #29
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  10. Grynch

    Grynch Long timer

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    If folks are wondering why I am lagging on the reconditioning of the bike, I am working on another Dam ( not damn) project. It needs to be done before the 15th of October, that is when the environmental permit expires. Come to think of it it is a damn project! To the right of the photo is a valley with a ranch on it, the Tomcat ranch, owned by Tom Steyer. IMG_20191003_125038522_HDR.jpg
    And gully repair at bottom

    Talking about old iron; I got thrown into the deep end with this old girl.. 50,000 pound machine 977L Caterpillar....This machine defined the U.S.A.
    IMG_20191004_152716375_HDR.jpg
    I know, I know it is not Moto related....
    IMG_20190925_144430948_HDR.jpg IMG_20191010_115126923_HDR.jpg IMG_20191003_144332773.jpg
    IMG_20190909_145658159_HDR.jpg
    Emergency outlet pipe. IMG_20190821_125512038.jpg

    Attached Files:

    #30
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  11. lineaway

    lineaway Long timer

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    That is not old. We have a 1932 Cat 50 at work.
    #31
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  12. Grynch

    Grynch Long timer

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    The old iron is better then the new stuff in some ways.
    #32
  13. Grynch

    Grynch Long timer

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    What do you guys push/ pull with that?
    #33
  14. Grynch

    Grynch Long timer

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    What two stroke oil is a good one nowadays?
    It used to be Silkolene was the go to oil for the two stroke road racers back in the 90' s. I have run Motul and Moterex I just do not like the price. I had was some Wall Mart stuff to start it. It looked like it gummed it up a little bit.
    #34
  15. Hoss Cartright

    Hoss Cartright 219.474.6657

    Joined:
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    You have an "early" 2001 model. Not all bikes came with "A" piston. Pistons at that time were made by Mahle and the cylinders were produced in the Czech Republic. A worker at GG measured and matched them into "best possible match" sets for production. I have seen "B" frequently, and even "C" as OEM pistons.
    Your piston was manufactured at the Mahle main production facility and built in the month of October 1999.
    test.jpg

    The "98" is most likely code for the 8th month of 1999 (the big bore models from 1996 through 1998 were 338cc and have a 0.5mm different cylinder deck-height for the 1mm longer stroke of the 338cc engine, as well as differences in the water exit port on the casting.)
    Your bike has a cylinder configuration of: 60mm stroke 327cc with early 2001 8mm head bolts and right-front-exit water port. Cylinder head bolt diameter and the head were changed to 6mm on the large bore bikes in mid-year 2001 to reduce failures of the o-ring seal. Year 2000 and early 2001 327cc cylinder heads were somewhat problematic as casting/machining variations would cause a small percentage of the cylinder heads to fail due to a break-away of the aluminum near the perimeter of the interior head o-ring on the water side of the machined groove and the o-ring would bulge-out into the water jacket and break the seal which would result in coolant leaking into the combustion chamber. Yours looks very good though and I would not expect it to fail at any time in the future.

    It is correct to grease the cylinder head o-rings as I show in the workshop videos. 8mm cylinder head bolt torque is 18 fl.lbs.

    I use #0000 steel wool for rust clean-up as it leaves scratches smaller than can be seen by the naked eye.
    #35
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  16. 2whlrcr

    2whlrcr gooligan

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    Oh noooooooooooooooooo….
    #36
  17. Grynch

    Grynch Long timer

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    Come on , it has TCW 3 in it, they would not let boats be stranded in the water.
    #37
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  18. tomatoe333

    tomatoe333 Long timer

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    Any good synthetic 2-stroke oil. Mix it 80:1. No richer than that.

    Even good quality Stihl chainsaw engine oil will work.
    #38
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  19. Sting32

    Sting32 Trials Evangelist

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    Um his OH NO was because there have been multiple threads about oils
    #39
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  20. Norman Foley

    Norman Foley Devotee of the Husqvarna Supporter

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    Walmart 2T oil? I used to ride snowmobile with a guy who used it, and his exhaust smelled like a Tomcat pissing on a hot expansion chamber! :eek7
    #40
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