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1979 It 175 neutral???

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Just got my 175 built, new crank, new piston and fired up friday ..yesterday I got the chain on and tookher for a ride and found that I was sterting out in 5th gear so I banged it down and went around the block and came back to the garage and noticed I did not have neutral 1 up from 1st gear. so I shut it off and found a neutral between 5th and 6th???

All the gears work good but the neutral position is wrong, I need to check the shift star behind the clutch and see if it is posible to rotate it 180 degrees, surely the gears only go in one way (inside the cases).

I have had other yamaha's that I have found a neutral in the upper gear range by not shifting positivrly enough.

Also the bike has good power down low and pulls really good then just falls flat with out the presents of the second wave of power that is written about with these bikes.

I am going to check the timing and the clip position on the needle.

anyone have info on the neutral problem or tuning the 79 IT175?

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I did the same thing on a 77 yz125 in 1980. Ya,your shift star is out of place. And i thought i'd never see that happen again!:smashpc: But back then i simply left it and rode it until it poped out of gear enough times to destroy a few things.

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well mine is not popping out of gear. the bottom of the it175 is the same as your 77 125. I will fix it today it only goes on 1 of 2 ways so it must be the other!!

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No if it is a stock muffler, (the one with a spark arrester) the part before where you pack it is clogged. they are a bugger to clean out. (I ended up cutting mine open and cleaning and then welding it back together.)

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I found the little turbo looking fin up towards the front of the silencer assembly and could not see but a little bit of lite through it so ....I lit it up!! this thing bellowed smoke for about an hour.

I started it up with a map gas torche once good and hot it kept itself lit up at first clamped into my vise but soon I had to move it outdoors, with a vise grip and the hitch on the back of the truckI mounted it and rid the nieghborhood of flying insects.

seems like it would help the engine breath easier and hope it helps the top end power.

thanks for the tip but I would rather not cut and weld and the pipe is clear now.

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I found the little turbo looking fin up towards the front of the silencer assembly and could not see but a little bit of lite through it so ....I lit it up!! this thing bellowed smoke for about an hour.

I started it up with a map gas torche once good and hot it kept itself lit up at first clamped into my vise but soon I had to move it outdoors, with a vise grip and the hitch on the back of the truckI mounted it and rid the nieghborhood of flying insects.

seems like it would help the engine breath easier and hope it helps the top end power.

thanks for the tip but I would rather not cut and weld and the pipe is clear now.

What this you forgot invite me over for that 2-Smoker Barque

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You may well have cleared it out.

see how it runs if it still runs crappy then just pull the muffler off for a quick test ride. (Just long enough to see if it clears up! your jetting will be off if you run without.)

I found the little turbo looking fin up towards the front of the silencer assembly and could not see but a little bit of lite through it so ....I lit it up!! this thing bellowed smoke for about an hour.

I started it up with a map gas torche once good and hot it kept itself lit up at first clamped into my vise but soon I had to move it outdoors, with a vise grip and the hitch on the back of the truckI mounted it and rid the nieghborhood of flying insects.

seems like it would help the engine breath easier and hope it helps the top end power.

thanks for the tip but I would rather not cut and weld and the pipe is clear now.

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maybe this thing won't rev to the moon?? anyone can tell me the pull on the rpm's I should expect??

there is a big pinch on the pipe about 8 inches up the header from the engine before it starts to bellow out

the reeds where making a harmonica type sound when I was turning the engine over before intital start up

need to check:

1. the reeds

2. the float hieght (need set pionts anyone??) mukuni 35mm detached rod float style

3. maybe cut the dented section out of the pipe and hammer back into shape then have welded back up (anyone around marietta ga a welder that would offer services to a poor white boy??)

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they will have a decent hit but as stock they are NOT like a YZ. Fix the dent in the pipe,

and like I said take the muffler off for a quick test. I burned mine out and still didn't get it all out. I had to cut it open to get it all.

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I am not sure if it was the float hieght or the lack of proper air filter but she runs out pretty darn good now almost as good as my kdx200 but not quite.

Now to get the sound levels down, I will take her in the woods soon but I think she will be a hybrid trials or street blaster if I can tag/plate it.

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Ive got a 77 IT175 that wouldnt rev out when i got it. the air filter wasnt the right one (guy had lost the cage and stuck universal foam over the intake hole!) I found a cage and the right filter and it revs to the moon with a very noticeable hit. The "shadetree filter" didnt have enough surface area and wasnt flowing enough air.

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I think that was my problem too..

Do you know of a rear shock that will fit that is rebuildable? I don't think the 77-79 are rebuildable...I have heard that the yz125 shock is rebuildable and that its a bit longer though

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Do you know of a rear shock that will fit that is rebuildable? I don't think the 77-79 are rebuildable

They are rebuildable....... If you can find the seals and o-rings.

A good suspension shop should be able to service the shock with no problems.

I replaced the fluid in my own shock, and just got a suspension shop to blow in some nitrogen to the correct pressure.

You can fit a YZ125E rear shock, it gives a little more travel than the IT item, and I suspect that the YZ125F unit will fit as well.

All the shock bodies are the same length from YZ125D through IT175D etc and even the IT425G, it's just a steel spacer inside the shock body that controls the overall length and shock / rear wheel travel.

If you intend to play around with the shock, make sure you release all the gas first ! No one wants to have a damper rod embeded in their head !!!

Dave R

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They are rebuildable....... If you can find the seals and o-rings.

A good suspension shop should be able to service the shock with no problems.

I replaced the fluid in my own shock, and just got a suspension shop to blow in some nitrogen to the correct pressure.

You can fit a YZ125E rear shock, it gives a little more travel than the IT item, and I suspect that the YZ125F unit will fit as well.

All the shock bodies are the same length from YZ125D through IT175D etc and even the IT425G, it's just a steel spacer inside the shock body that controls the overall length and shock / rear wheel travel.

If you intend to play around with the shock, make sure you release all the gas first ! No one wants to have a damper rod embeded in their head !!!

Dave R

I studied my shock pretty good an did not see the typical signs that it would come apart.

How did you get nitrogen in there Mine has no schrader valve

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The Krizman (turbine looking thing) device is tough to clean when they pack up. Run synthetic oil in the future and you'll never have to do it gain. In the old days, when we were putting SuperTrapp clamp ons to have a spark arrestor on YZs and such, BelRay MC1 was one of the few that wouldn't clog the ST disc pack.

I used to soak my spark arrestors in gas for a few days to soften up the carbon, then light them off in a burn can, with a supply of nice dry wood in the bottom. I would place it vertical so the flames would shoot up through it. When the thing cooked for a few hours and was glowing a nice dull red in the coals, drag it out and toss it in a bucket of water. All the carbon remaining just falls off. Then a quick spray with the BBQ paint, repack and go. Once you switch to a good synthetic, the carbon is soft or slimy, so no more build up. You can soak in mineral spirits for an hour every time you need to repack, and that's it.

I've gone over to the dark side now (FI four strokes) so no longer have to do this. But it works as well now as it ever did: I helped a friend clean his pipe that way about a year ago. Works for the entire expansion chamber if needed.

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I studied my shock pretty good an did not see the typical signs that it would come apart.

How did you get nitrogen in there Mine has no schrader valve

You can replace the stock rubber center nitrogen fill port with a schrader if you like. I did that to my YZ, and took it apart every season to change the oil and refresh the nitrogen.

They use a pipe thread (or did) on the port, so carefully unscrew the original (very carefully, just enough so it begins to leak down) I REALLY MEAN IT ABOUT THE CAREFULLY. BE SURE IT ISN'T AIMED AT ANYTHING. And use soapy water or leak detect to see that you are letting it leak down. Even a slight leak will drain it in less than five minutes: no volume to speak of. If you have one of the older needle fill setups, you can use that to drain off the pressure. Again: be real careful: if it gets away from you it can put a hole in a car door! They will launch really really well.

After bled down, replace it with a schrader valve with a pipe thread end. You can retap to pipe thread if needed.

The shock itself will come apart after you bleed off the nitrogen. Remove the spring. Pull up the seal cover, and there is one of those round wire rings that acts like a snap ring. Press the seal assembly down, and you can carefully get the ring out; then the whole thing: seal head, and shock innards, will slide out. Before you do that, be sure there are no burrs on the inside of the shock body where the snap ring just was removed from, as it will score up the o-rings and seals as you pull it apart. 220-320 grit wet Or Dry will fix any nicks you find. Having the remote reservoir makes it easier. The trick it to get it back together, and get all of the air out. We used to use large syringes with a blunt needle to fill up the shock body, then do the same with the hose and remote. Last, install the schrader valve, change with nitrogen (I think we did them at about 225 PSI) and away you go.

Race Tech can rebuild these for you with one of their Gold Valves, and is very worth it if you're going to keep the bike and use it on a regular basis. I think Moose sells the seal heads. Be sure to deburr everything before reassembly, so no seals/o'rings/etc get scratched upon assembly. Like I said: I rebuilt my old YZ shock and forks every season. The soft aluminum shock body particles would rapidly contaminate the oil, so a frequent change was mandatory for proper operation. I got rather good at it. the first time is the hardest, then it is vastly easier from there. Go slow and don't scratch/gouge/nick anything.

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