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Fantasy
Edited Date/Time
11/23/2018 6:31pm
I remember reading in a thread that a bunch of guys liked this combo, but I can't find that topic.
For those that have tried it, what are your thoughts? What did you like and dislike about the combo?
For those that have tried it, what are your thoughts? What did you like and dislike about the combo?
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I like the stock exhaust, no reed block spacer, Rad Valve, Power Wing, and 9oz. FWW. And I keep the stock gearing.
This gives the bike some bottom, lots of mid, and some top for a functional powerband.
Removing the spacer should work regardless of the block used.
I like the freedom of not having to shift and using a gear a little bit further. Even with the spacer removed and a 9oz. FWW, I do not feel that any bottom end is missing. I could probably ride in 3rd gear around most of the track just like a 450 if I wanted to. But I like using second in the tight spots and lugging 4th in the high speed spots.
And if you have a stock pipe, give it a run with the PC muffler and see how you like that if you haven't already. They can be picked up pretty cheap too on the used market
Pit Row
I continue to read people say otherwise - but havent seen anyone publish a test showing removed its better
Ill retest it next yz I have for dyno work and try to republish it- but just throwing it out there on my experience with it. Ive done somewhere around 3000 yz250 dyno pulls to date.... and tested just about everything you can name.
Curiously - most of the time a short or long pc vs pc dynos the same. Often the stock silencer dynos the same as some of the aftermarkets
Years ago after seeing this, I cut an oem silencer just before the second mount bracket turning it into a 1 mount bracket set up, redid the end cap just like oem (quite the pain in the rear)- and redynod. Got the same I had before it was cut but a lot louder sound - and road it like that for ages - people always commented how good it sounded, looked at it and at quick glance you could see the confusion on their face since it looked stock
The biggest current influence ive seen on the silencers is the outlet size. The pc and some of the fmfs have a reduced outlet that builds more heat - and helps over rev - sometimes power too a smidge.
But imho the biggest difference between the stock, long aftermarkets and shortys is the sound..
They would learn a lot...
If it does, I'd rather have a more usable powerband and lose 1HP. Usable and easier to ride makes a bike more pleasurable to ride to me. I ride for fun! My racing days are over, and I'm ok with that.
Vet riders and such probably will not notice a slight loss of horsepower. And one could argue that too much power on a two-stroke will make the bike harder to ride and result in less consistent lap times.
I remember Dubach saying that Bradshaw tried a stock 250 and liked it better than his race bike that had 11 more HP. Delivery is more important than a number on the dyno.
I say go for it. Nothing beats the sound of a well tuned two stroke with R304!
I had the head cut, PC pipe/304, Boyseen RAD valve(no spacer) and 9oz FWW and it will tractor. It’s surprising how it will lug from idle and runs very well everywhere. Like you said it’s a 3-4 gear bike all over the track.
I went with the RAD valve because of the stock cracking boot, bought it as a “blem” from Boyseen for a great discount, I believe the blem was the sticker had a wrinkle in it. I couldn’t find any defects.
I may bump to a 51 rear, but it’s working very well 14/50.
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