450 HP Numbers


73 replies to this topic
  • RADRick

Posted September 24, 2005 - 01:50 PM

#61

56 SEEMED high but who am I to argue, I'm pretty new to all the dyno stuff.

I'm not. 56 is way too high. A stock YZF450 comes in about 45. You would have to do a lot to get 11hp more out of it. Also, are you using a street tire when dynoing or the stock knobby? You'll never get good numbers with a knobby due to tire slippage on the drum. Where are you picking up your RPM from? It matters with a CDI. Also, without the correction factors, the results are useless since they don't take into account humidity, barometric pressure or other things that affect the results. In looking at your graph, I see another problem. From 7000 on up the line is erratic. That usually indicates either an electrical problem (spark breaking up) or a fuel problem (too lean). Whatver you true numbers are, that part of your RPM range is useless since the engine is obviously not running right. After years of testing motorcycle products I have come to one conclusion: dynos can lie, if you want them to.

  • B86_Racer

Posted September 24, 2005 - 11:12 PM

#62

I was using a street tire. I believe that the line is eratic up in the upper RPM's because my wheel has a hop to it. I've already remedied that.

Also, what do you mean without the correction factor? I've gave you the correction factor and it was figured in to every run that I did. :banghead:

I'm not trying to be an ass or anything but like I said, I'm new to dynos.

P.S. I didn't want my dyno to lie! :applause:

  • yfzut

Posted September 25, 2005 - 06:34 AM

#63

does any body think its possible to get 60 horse out of a 02 yz426 with a 444 big bore and a 2 stroked crank, some good port work.

  • Ron Hamp

Posted September 25, 2005 - 01:46 PM

#64

its been done before 60 rear wheel hp out of a stock displacement 450 the 426 should also be able to do it .

  • GENE426

Posted September 25, 2005 - 04:01 PM

#65

its been done before 60 rear wheel hp out of a stock displacement 450 the 426 should also be able to do it .


thats 20+% increase
what was done to it?

  • RADRick

Posted September 25, 2005 - 05:32 PM

#66

I was using a street tire. I believe that the line is eratic up in the upper RPM's because my wheel has a hop to it. I've already remedied that.

I use tie-downs on both sides of the bike to keep the wheel hop to a minimum. The problem is with an unbalanced street tire on a narrow dirt wheel, you can only do so much.

Also, what do you mean without the correction factor? I've gave you the correction factor and it was figured in to every run that I did. :banghead:

Does the dyno have the auto-update of the Corr. factor? Is it measured inside or outside? Was it the same for every run? It matters. Booth design is very important. That's why I put zero faith in charts from open-air dynos (like White Bros. uses at events). Accurate measurement requires a controlled environment.

I'm not trying to be an ass or anything but like I said, I'm new to dynos.
P.S. I didn't want my dyno to lie! :applause:

Dyno results are only as good as the people operating them, which is why we take them with a grain of salt. When I test, I always do at least 3 runs to verify repeatability. I also try to do all my testing within a 2-3 hour block so that weather conditions have less chance of influence. Even then, the results are only good for that day and those conditions.

When Dirt Rider tests include dyno results, they are a very small part of the overall picture. Dynos can't tell you which bike will pull harder out of turns, or which bike will scream down the straightaways. They are a good tool for finding improvement and verifying what mods work, but they are a poor choice for deciding which bike will work best in actual riding conditions. We would never base a comparison of a bike or a product strictly by a dyno run. Dynos are best when used to find problems or to make comparisons between products/modifications. They can't predict how a bike will perform in the real world. There's just too many other variables involved for them to do that.

  • B86_Racer

Posted September 25, 2005 - 08:13 PM

#67

Yes the CF had an auto-update as I had different CF's for each run. Some of them were the same CF but that's just how it worked out. It was a enclosed dyno and the measurements came from inside the booth. My main objective when using the dyno was just to get the bike jetted properly on the dyno with an a/f meter. It's jetted perfect now! :applause: I could really care less about how much HP I'm making but I'm more interested as to why my #'s could be so high. There's so many variables in dyno runs it could be a number of things it seems like. But I've talked to my instructor about the runs, etc. and he said that they are correct and the dyno is setup properly, etc. I've actually been told that by more than one person. :banghead:

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • kcander

Posted October 06, 2005 - 03:15 PM

#68

thats 20+% increase
what was done to it?


He slapped one of those aforementioned SV650 motors in it. Easy!

  • speedy114

Posted October 06, 2005 - 08:13 PM

#69

RC's 450 is pushing 69 HP. and i dont care if you dont belive me its true.

  • GENE426

Posted October 06, 2005 - 08:17 PM

#70

RC's 450 is pushing 69 HP. and i dont care if you dont belive me its true.

69 good number
man that alot oh hp if its true! :lol: :lol: :lol: :banghead: :banghead: :busted:

  • FFRacing79

Posted October 06, 2005 - 08:56 PM

#71

RC's 450 is pushing 69 HP. and i dont care if you dont belive me its true.



:banghead: :banghead:

  • GENE426

Posted October 06, 2005 - 09:17 PM

#72

:banghead: :banghead:


I WONDER HOW HE FIG THE HP OUT
TOP SECRET

  • tp3dxf

Posted October 06, 2005 - 09:41 PM

#73

What kind of horsepower are you guys' 450's putting out? Mine isn't quite jetted perfectly (should be after tomorrow) and i'm putting 54.5 to the rear wheel. Running a Bill's Pipe and U4. I know some of the *very* modded motors are putting out 60+hp.

Anyone got any dyno #'s? I should have some charts by tomorrow


Good question. But the answer should be what can you do with it?

I love HP but how much of it do I really use?

Out in the dez I have seen 125's beat everthing in the right hands. Rare but true.

I don't care how much HP a bike makes. It's all about the rider. Unless your drag racing.

  • GENE426

Posted October 06, 2005 - 09:46 PM

#74

Good question. But the answer should be what can you do with it?

I love HP but how much of it do I really use?

Out in the dez I have seen 125's beat everthing in the right hands. Rare but true.

I don't care how much HP a bike makes. It's all about the rider. Unless your drag racing.


YUP I THINK YOUR RIGHT





Related Content

Forums
Photo

2016 YZ450 by CaptainKnobby


Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

Is it worth it? (Cam and High compression piston) by macgi77


Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies
Forums
Photo

Megabomb Fitment by 288yz450


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply
Forums
Photo

Michigan Motocross Tires by 288yz450


Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.