badmotofo

Upon further inspection it appears the last gear on the main shaft is making contact with the case. Also, the circlip at the end of the shaft appears to be touching the case as well (see indicated areas in photos.) This leads me to believe that there is a thrust washer missing that would rest against the gear and push everything on the shaft slightly away from the case. However, between the Haynes manual and online parts diagrams I see no indication of a thrust washer that would go there. Whats more, I also cannot find a reference to the roller bearing that sits in the case. So…

There is much resistance. It doesn't want to go past second.

For a Covid project I completely disassembled my 1976 TY175 and rebuilt the motor with new bearings and seals as well as going through the rest of the bike. I had some concern with the transmission when I initially rebuilt the motor, and, when I put it all back together and started it up I was only able to locate first, second and neutral. I have the motor disassembled again and I am trying to figure out what I did to cause this to happen. Prior to initial disassemble the tranny was notchy but shifted through all six gears. Currently, I have the transmission mounted in the left-side cases. In attempting to rotate the shift drum I have difficulty getting through all the gears. I also tried rotating one of the shafts to assist in gear movement but still something does not seem quite right. The shift forks are in the correct order. The transmission itself was never taken apart. And there does not seem to be any missing washers. So, I'm just throwing this out there to see if anyone has had a similar experience and/or a suggestions to try something that I haven't thought of. Thanks,

Much thanks!

I have a 1976 TY250. It's missing the heat shield '250' decal and I have not been able to find one to purchase. My plan is to create this decal – it is white on clear. As my bike is currently stored away from my house, I'm asking to see if someone can measure the heat shield decal area on the heat shield – specifically the height. I believe the heat shield is the same on all models (though I may be wrong). I plan on making a bunch if anyone else needs one. I believe the same decal is used on the left-side plastic cover. Thanks,

TY250 forks/front end are more available than the 175s and are heavier duty/larger in size.

Urban trials – that's great! I wish I had just some little piece of something to go and put around. No such luck in the SF/Bay Area.

My TY175 had a poor performing front brake. I messed around with it for some time and could not get it to improve. I finally ditched the aftermarket brake cable I bought and went with a Yamaha OEM brake cable and the brake works so much better.

I thought I'd share. Great exposure. I love the bike.

Thank you for the information. I didn't think of taking the holder off to install the cable. It fits perfectly and I'm pleased to say I now have front brake stopping power on the 175. Time to order an OEM cable for the 250. Next thing to do on the 175 is figure out why on throttle chop the motor (I'm looking for words here) doesn't fall gracefully into low revs but will surge _ where the revs go up and down. My hunch tells me its fuel delivery but I must inspect.

I have a 1976 TY250 and a 1976 TY175 with 250 forks. Each bike has the same issue with very poor front brakes. Holding the brake arm by hand locks the wheel pretty good – though I know it is not the same as when under riding load. My feeling is that the issue is with the cable. I purchased an OEM front brake cable for the 175 (the 250 is stored elsewhere at this time) as the old one had snapped at the perch as I was muddling with trying to get the brake to work better. The old one was not OEM. Oddly, The new cable does not fit into the 'Cable Joint' that is attached to the brake arm. The slot is too narrow. Checking part numbers, the 175 and 250 run the same cable. I ordered and received a 434-26341-04. However, the the cable itself has 4344104-5A08 printed on it. (??) I am hesitant to open up/drill out the slot in the cable joint. But, I'm hoping that installing this cable will give real braking power. Also, what is the correct direction for the cable joint to be mounted? Slot opening facing front or back? Thanks,

I did finally come across a large piece of pipe with a wide enough diameter to slip over and bend it back into place. My next task to figure out a way to make my TY250 and my TY175 with 250 forks stop. Both front brakes work at around 30% of what they should. I have found this to be quite a disadvantage competitively!

Might want to check the muffler. I've seen your situation remedied by replacing goo'd-up packing.

Thanks for the photo. It looks like my problem was that I installed the large part of the anti-bottoming socket backwards. It now fits together as it should. Thanks again.

feetupfun, here are some photos of the forks. I bought these off eBay with the intention of fitting them to my TY175. I'm not sure what year they came from. The online parts diagram from yamaha looks different from this.

My forks have been apart for a couple of months and I am not positive how the front fork is reassembled. Could someone confirm? Right now I have the damper inside the slider and extending through the bottom of the slider. The small spring and aluminum cap are then put onto the damper and the unit is inserted into the outer fork. I tried it with the small spring inside the slider but the slider would dig into the aluminum cap. Thanks,

I purchased a 3/8" drive adapter for my impact driver / "rattle gun" and it came right out. Thanks for the help,

Trying to remove the piston from my front forks. I believe I need to hold the top of the piston while unbolting from the bottom. My 175 has a stub and I customized a socket to hold it. The 250, as well as I can see, has no stub and my tool does nothing. Does anyone know a good method to hold the top of the piston? Thanks,

Yes, I should try a new plug. That's why I like these forums – remind me of the obvious things that I overlook. The bike has electronic ignition. Thanks,

Does anyone out there have a spec on the proper compression reading for a TY175? My gauge showed 110 ft. lbs. Curious to know if that is low or adequate. The bike started running poorly although seems to have decent power. Symptoms are occasional backfiring, some surging on throttle shut-off and possibly a touch of pre-detonation (I'm not exactly an expert at knowing what I'm hearing). Air filter is clean. Time for rings? Bad gas? Any advice appreciated. Thanks,

Poole let me borrow an old TY80 (painted to look like an AJS). No reg. on it so it's hard to take out locally. I need a secret trials training center!!

The switch that was on the bike (not stock) and the toggle switch I tried (came from a dual sport kit) both have a black wire (male) and a ground. The bike as I received it had the black disconnected and the ground fastened to the frame. I'm not sure about open- and closed-circuit connection switches.

Long story short, connect the kill switch and no spark. Depress the kill switch and there is spark. I connect a toggle kill switch and it has spark in the off position and does not in the on position. The bike is a TY80 for kids to learn on so I would like the toggle switch to read correct. Somewhere it appears some wires have been crossed. Anyone familiar with this issue? Ideas of what might be causing this? Thanks,

btc273: Judging from the photo, albeit small, but I see the GoPro, the location and the three 175s, I presume this is Barry. Thanks for the info. I still need to arrange to meet up with someone with a press. Hope to see you again at Pt. Arena or some other AHRMA trials in 2014.

Spinner replied to my similar question (11/16/12) when I was looking for a right-side without the oil pump clutch cover. It took a while to find but the cover with 537 casting number bolts right on and looks great. The cover that bolts right on fits 1974- 77 yz125, 1976 yz125x, 1976 YZ175, 1976-79 YZ100. PART ## is 537-15431-01-00, there is a casiting number 537 inside the cover. Cover with casting number 1W1 will fit bit need a lot of modification!!!