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jwriott

GYRT Insert Disassembly?

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Has anyone tried separating the steel section from the aluminum and running the bike with just the aluminum insert installed?

I was mostly interested in getting the 2 pieces apart. Yamaha used some sort of green Loctite (648?) which I'm sure will be a bear to remove.

Thanks,

John

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John

I made a brief attempt by setting the insert on the edge on an anvil and using a sledge hammer and large punch to try to knock out the steel tubes. It didn't budge after a few hard strikes so I quit trying as I thought I might damage the aluminum insert.

I couldn't see what was holding the tubes in place, but it was holding well!

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I know there is a bolt holding the insert and steel tubes together. Did you remove the bolt?

I assumed it's a press fit so I was going to try heating the aluminum end with a heat gun before knocking the tube assembly out. I just wasn't sure about the bolt.

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I did remove the bolt before trying to knock out the steel tubes. Heat is a good idea but be careful as I suspect the aluminum may be easily damaged by heat. What are you referring to as a "heat gun"? I was going to use an acetalene/oxygen torch.

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Ogrebelle is right, basically a hair drier on steriods. Since the aluminum transfers heat more quickly than steel, I was going to heat the aluminum end quickly and try and knock out the steel section. If the steel started to heat as well before I got a chance to knock it out, I was going to set the steel tubes in cold water while heating the aluminum. My other thought was to put the whole thing in the freezer, then heat the aluminum.

How did you get the bolt out? Heat it or just remove the bolt? :)

The heat gun shouldn't get hot enough to damage the aluminum. An oxy/acetalene torch probably can.

Well, I got the bolt out no problem. Tried to knock the tubing out like you tried to and it didn't budge. I used a heat gun on the aluminum again, and took a 3/4" drive with a 3/4" socket on the end and inserted it into the aluminum cap. 5 good hits and out it came. It's just pressed in.

I'm going to try running the bike with just the aluminum and see if it still fouls plugs. Hopefully, it's quieter than fully open.

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Good work! Let me know about the sound and performance with just the aluminum vs. fully uncorked.

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I'll report back after I get my air filter back in. I cleaned it the same time as I was taking the insert apart and needed to let it dry.

I figure if it doesn't work, I'll stick the steel in the freezer and heat the aluminum and put them back together and play with the jetting until I get it right.

:)

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Off the topic, where the hell is Alva?? I grew up in Wyoming and thought I had been everywhere. I will better know about the insert as I pick mine up Thursday. Thanks, Dirtstiff :)

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Alva is near Hulett which is near Devils Tower in northeast Wyoming. I'm not actually in Alva, we just get our mail through the Alva post office. I'm on a ranch about 10 miles from the Montana line and 15 miles from the South Dakota line. No sound checks here but the cows think the wr is a little loud uncorked! :)

Where in Wyoming did you grow up?

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Check your' p.m.'s Wayne. I pulled the baffle out of my WR last weekend and was totally impressed with the power. I hope the GYRT insert works as well as being un corked. :)Dirtstiff

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I bought the pro moto insert [ same price] and i thought it ran great , low end was great [ i ride tight woods ] just a lot less noise .

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I put a ProMoto insert in my WR yesterday and it is quiet but lost power throughout the whole RPM range. I had been running a YZ426 silencer with ProMoto S/A and quiet insert. With the YZ setup it ran great but louder than when it was on my YZ426.

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Have you tried to re-jet ? some guys are saying that they need to re-jet [ leaner ] and that get's the 450 running rite . i must have been luckey because my 400 run's great . Some also say they need to re-jet for the gyt-r insert . The gyt-r was my first choice but it was on back order for a long time that's the reasion i got the pmb insert .

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Well, I finally got a chance to ride with just the aluminum piece from the insert. It's quieter and doesn't feel like I've lost much power. I also haven't fouled a plug and I started and rode it 3 times so far.

I pulled the insert in and out while running to see if I could tell a difference and it is noticeable. Not as quiet as the full baffle but better.

later,

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I took the bolt out. Then I used a heat gun and heated just the aluminun. Then I placed the tubes inside a piece of pipe and used a 3/4" socket and knocked the steel section out.

If you need to put it back together, put the steel in the freezer and heat the aluminun. It was just a press fit.

smashpc.gif

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I know I'm a little late joining the disscusion, but what is the long term report on running the modified insert? I tried the normal GTYR insert and it lost low end and was too rich at low end.

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Vmaxcbr900wr426,

With the pipes out, what db do you think its running? lower than 98? In Cali the law is 96 but... 97.5 is passing.

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Not sure about the DB level. I'd say you're close.

It's very easy to take apart. Pull the bolt and put the thing in the freezer. Take it out, heat the aluminum only with a hair drier or heat gun. Place a socket in the end and support the aluminum half, give it a small whack and out it pops.

To put it back, freeze the steel tubes, heat the aluminum and push it together. You can use a little WD-40 to make it slide easier. It's just a press fit.

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