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'92 YZ125 Woods Bike-Rad Valve?

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Hey Fellas, just sharing a project and looking for a little feedback...:thumbsup:

A friend needed cash so I bought his basket case 125 for $200.:lol:

Traded some TIG work for a motor freshen w/Wiseco piston.

Scored a used FMF Gold pipe and silencer.

Two things weren't in the big box o' parts:

-reed cage/carb boot

-front sprocket/bolt/washer

Used stock reed cage/boot on feebay usually runs about $80-90. There's a Boyeson Rad Valve on there now for $100. Will these older bikes see a more dramatic difference with an aftermarket reed than the new stuff?

As far as front sprockets go,I was thinking of dropping a tooth for better woods/trails manners?

Any opinions/thoughts/input are welcome and appreciated. My KTM is obviously my main ride,this will be the spare/friend/when the kids get big enough bike.:ride:

Thanks,Sean

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It would be a tough call for me at the minimal price difference your seeing.

but If I was using the bike for the woods i would prolly go for the oem setup. I added a boysen rad valve to my cr250 and i found it to add alot up top and sacrificed quite a bit on bottom. It was one of my favorite mods to be honest but i dont use my cr in the woods.

of course dont take this as gospel since all bikes are different. This is just based on my experince.

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Yeah it's hard for me to pass on the fancy shiny new aluminum part for $10 extra over the dingy used stockers:D

But if it's gonna make the bike a turd for it's intended purpose I might hafta pass.:thumbsup:

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Stock reed setup was junk that year OEM reeds was to soft stock they always recommended doubling the stock reeds to get bottom end snap I bet the Rad is better then stock I have a few dirt rider mags that did tests of 3 different modded YZ's there was a many of those tests. Seeing a stock one was rare known for a weak motor but great handling chassis with lots of money thrown at it could be made faster. the 91 92 93 YZ 125 probably holds the rep as the slowest YZ 125's of that decade last of the YPVS rotating drum design. Most nagged about flaw airboot would flex on hard jump landings which allowed the carb to hit the cases and it would bog out sometimes. Anyone remember the pic's of emigs 92 YZ with all the extra bowl chambers to stop this.

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I prefer stock reed setup for all applications... but as far as the 12 tooth front, I use it for tighter woods riding and love it! easy fix if it doesnt fit your style

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What year is your bike?

From what I've been reading,the newer bikes have pretty good stock stuff,but there's very little info on these older bikes on the site.

The little info I have found leans towards earlier bikes needing all the help they can get...:thumbsup:

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That was actually VERY helpful:banana:.

I guess my next question is how I track down the power valve parts he recommends.

I looked in the OEM parts store but I admit I'm a little lost as to which powervalve parts he's referring to...:thumbsup:

http://shop.thumpertalk.com/oem.asp?partcategory=15393&manufacturer=6&category=3&year=1990&model=388

Am I even looking in the right place?:ride:

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Oh the ramp cup mod that is listed it's that is part of the power valve mechanism that is located inside the rightside of the case.

should have a part that has groves that typical is 4 metal balls that spin outward in the ball ramp grooves as the motor revs it forces the spring loaded plate to open which causes the power valve linkage to move / open on the cylinder.

The spring tension and the shape the groves of the ramp or the Ramp cup can have a slight change on like what RPM it starts to open at.

So when he says buy this ramp cup I believe it is part # 19

http://shop.thumpertalk.com/oem.asp?partcategory=15404&manufacturer=6&category=3&year=1990&model=388

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