A Motor's Worth

Racer51

New Member
May 19, 2011
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Northwest Ohio
Now I know most of you go through ken O connor or F7 or VF3's on your motors. They Duncan Racing International claims to make a 50-60% improvement ofer stock. I did the math and if a stock motor makes about 20hp peak and you add 60% to that it's 32hp. Is that a lot to a blaster for the money, power and parts your getting for your money? They also claim to have a 30 day money back guarantee on any part(s). Should I give them a try or can any one else give me any one who else who does this stuff for under $1,300 I know I could piece together a quad for less but it's all there and ready to put on and there's no guess work. Also would like input about the bare steel...cause to add a chrome job is $120 extra. I

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The Blaster in it's stock form makes 15 – 17 HP. These are the numbers that Yamaha advertises. If Duncan is claiming a 50% - 60% increase in power, it's probably true but nothing to brag about. If we add 60% to a 17 HP engine, we end up with 27.2 HP. One of our members, R and S Polishing from Oregon, raised his exhaust port 1 mm, cleaned up some casting flaws and tossed a re-chambered head on a piped, stock carb Blaster and made 28.5 HP. He had it tested in Oregon and posted his sheets here.

http://www.blasterforum.com/engine-13/oconner-mods-39899/

I was not involved in this testing and didn't know he was going to do it when I cut his head. I think spending $1300 for a 60% gain on a Blaster is a lot of money.
 
most of our resident builders are producing low to mid 30 hp. numbers with aggressive trail porting for way less loot than that
 
Whell here is my build list and the parts/prices I can get them for that I really want to go cause I testing the waters on motors.
Total Money I have at my disposal but dont want to have to use it all $1400
2004 Blaster-$400
Wiseco piston kit minus gaskets-$84
Vito's +3mm stroker-$159.95
VForce 3 reeds-$116
Toomey B-1-$359.99 comes with filter and all new jets for a stock carb.
Total $1119.94

I'm not adding prices on putting the thing together or porting cause I can do quite a bit of it myself and if i do id have to add a host of other things and I want to keep the motor self explanatory and simple for right now. So I'm going to do all the work myself on this one and keep you guys informed the whole time on a seperate thread when I do get it which should be a week or 2.............
 
I can only tell you what I would personally do...

If you're trying to get the most out of your setup on a budget, you need to think budget minded. A lot of power can be gotten out of a stock stroke stock bore engine if you do your modifications smart.

Unless your stock stroke crank is shot, I would forget the stroker for the moment. I would get the top end ported, a good pipe (toomey is a fine choice although I wouldn't buy one brand new), and an upgrade carburetor. An OKO 30mm or a PWK33 would work really well on a stock bore stock stroke blasty engine. I would also dump the Vforce reeds unless you get a bitching deal on them... They're not worth their price. Get a set of Boyesen dual stage reeds and rock on with the extra $80 in your pocket.
 
Thats what I'm all about I'm just showing the pricing on the high side to be prepared. The bike In question "wont start" is what I'm told but for 400 bucks It's kinda a deal where ya gotta get it and feel out whats wrong and what you can do to save it on the cheap.I dot know if it does need a new rod but was facinated with the idea of a stroker. The first things I gonna do when I get it is a compression test new sparkplug and new gas. and If it runs I probably not fiddle dick with it untill it blows it's top off. Ummmmm..........i did see VF3's for the lowest I've seen $116. If not I saw pro series reeds for like $48 shiped I have an OKO twist throttle on my other one and works great. I can get a toomey for about $320 new via coupon. and as for porting is there a term for getting power all throught or is there only sections of the power curve most can do?
 
Everything with porting is a trade-off. You have to concentrate where you're trying to gain the most. Toomey is a mid-top end pipe so a rather aggressive port job should be the thing to shoot for. You'll se the MOST gains at the top of the RPM range.

If you get your head modified at the same time, you won't loose TOO much power down at the bottom because of the better combustion and raised compression that's possible with a rechambered head.

Get the quad in question and get it to run like it is. THEN start modifying it... You may get it and find out it has a huge hole in the case from the piston fragging. One step at a time young padawan!
 
Will do quick question so if i got the toomey would it make sence to get porting for the bottom/mid since it would "even it out" and add power down low where I would need it? or would you simply recomend a better carb for that?