Author Topic: summer projects (Read 10711 times)

rsss396 · « **Reply #30 on:** August 03, 2014, 09:24:48 AM »

My last time at the Dyno testing the arctic cat/saber/liger reeds I tried the VF3 early and late versions.
the Early version is a 4pedal design(16total) and comes with reed stops and a removable stuffer
the Later version is a 3 pedal design(12total) and comes with a molded in stuffer and no reed stops

i was told along time ago that the Early version was the one to have and Not to run the stuffer. Many people do not run them in the sleds and when I picked up a used set they had been removed, so I was not able to make a test with and without them.

So what I found was the Early VF3 unmodified but with no stuffer made the same HP as the Late Vforce 3
I then heated and bent the plastic reed stops on the Early VF3 so that when installed back into the cylinder they actually rubbed top and bottom of the intake track.
Power went up 1 HP at peak so getting excited I decided to remove the stops ( I left about 1/4 of it still on because I crudely cut them while at the Dyno and did not want to hit the pedals with the cut off wheel )
well power went dropped back down 1 hp to being equal to the stock VF3 early and late models

All in all I seen less than a 1% change in my testing since the bike made only 1 hp more in a 110hp motor

udontknowme · « **Reply #31 on:** August 03, 2014, 12:37:46 PM »

if it does any good im thinking it will be small like you were saying. hell it might not even be noticable. probly have better results changing out the small stinger to a bigger one. i did find out one thing for sure though. that last cylinder didnt pull worth a shit below the pipe. after i reported a new one it pulls million times better below the pipe and doesnt seem to have lost much off the topend. not as much as i figured it would anyways. the timings are still somewhat low so i can make changes later on

toydoc · « **Reply #32 on:** August 04, 2014, 03:51:30 AM »

With the spacer under the stopper, it moves the flex point to one spot, that edge. That effect on the reed will feel like the stopper is removed and is just hitting the roof. Not sure if thats the way to go for power or reed life (hasn't worked for me anyway).

udontknowme · « **Reply #33 on:** August 04, 2014, 08:46:54 PM »

since every engine is alittle different i try not to assume a particular modification will or wont work on all engines before its even tested. its best to just try it and see what happens. atleast thats my thoughts anyways. its simple to take the spacers back out if theres nothing to be gained

toydoc · « **Reply #34 on:** August 05, 2014, 04:15:34 AM »

Good point. Just throwing out some stuff to help.

The mod will work (add gap), but no reed is happy flexing on a edge back at the screws, on any motor.

rsss396 · « **Reply #35 on:** August 05, 2014, 08:03:33 AM »

I agree with doc that there better approch would have been to have put more bend in the stoppers for reed life

Jerry Hall · « **Reply #36 on:** August 05, 2014, 11:52:16 AM »

Quote from: udontknowme;40314

if it does any good im thinking it will be small like you were saying. hell it might not even be noticable. probly have better results changing out the small stinger to a bigger one. i did find out one thing for sure though. that last cylinder didnt pull worth a shit below the pipe. after i reported a new one it pulls million times better below the pipe and doesnt seem to have lost much off the topend. not as much as i figured it would anyways. the timings are still somewhat low so i can make changes later on

Many of the Honda CR had back stops that were shaped in a manner to simulate a spacer strip between a conventional stop that had the curvature of the back stop tangent with the clamping area.

The theory was to allow the initial (low lift) tension of the petal to be low and then the tension increased as the petal made contact with the curvature of the back stop. I never saw any abnormal petal failures on the OEM Honda reeds that had this feature. I saw a lot of failures with some of the aftermarket reed petal kits that had too thick of a spacer strip.

Jerry Hall · « **Reply #37 on:** August 05, 2014, 12:00:11 PM »

Different types of reed petals and reed block do have an influence on the shape of the power curve but not as much as most guys are expecting. Most of the time you cannot feel the difference between different reed configurations, but the dyno will show these small differences.

The shape of the power curve is primarily controlled by the pipe and porting combination, not the reed valve configuration, unless the petals are floating at high RPMs or the petals are so stiff they will not open enough to provide the necessary flow.

Counter Sprocket · « **Reply #38 on:** August 05, 2014, 06:38:50 PM »

Are v2 better than v3. I see a lot of v3 users, not v2?

udontknowme · « **Reply #39 on:** August 06, 2014, 12:03:00 AM »

Quote from: Jerry Hall;40401

Many of the Honda CR had back stops that were shaped in a manner to simulate a spacer strip between a conventional stop that had the curvature of the back stop tangent with the clamping area.

The theory was to allow the initial (low lift) tension of the petal to be low and then the tension increased as the petal made contact with the curvature of the back stop. I never saw any abnormal petal failures on the OEM Honda reeds that had this feature. I saw a lot of failures with some of the aftermarket reed petal kits that had too thick of a spacer strip.

i assume you meen something like the oe cr500 stoppers. it has has a step near the front where it screws onto the cage. if my thinking is correct this would simulate a spacer being under the stopper and probly allow the very front of the petal to lift slightly more than if it were using standard continious arc stoppers

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ive thought about this spacer idea numerous times lately. looked it over 100 times. even with the spacer, the reed still seems to bend at a fairly gradual arc near the front where its screwed onto the cage. even if you look at the pics you can see it doesnt kink the petal. now if there were 2 spacers installed i could definatly see it trying to kink near the front. thats the great thing about forums with sharp people. you can get more sets of eyes seeing stuff you may have over looked.

i know alot of guys dont believe in simulators and i dont consider them the final word either but i think they can be another good tool to use along the way. my ktm reed block was showing very good results lifting the reeds 2mm more on the sim although i havent got around to messing with it yet. i know this aint the ktm and the cage is completely different in dimension but still i think the cr5 petals are underlifted. when you look at every aspect of the stock engine it screams longevity, not performance.

i did fire the engine the other day after i installed the cage with spacers. sounded good. but wether it runs well is another matter. ill have some kind of a answer over the weekend and report back what i find

udontknowme · « **Reply #40 on:** August 09, 2014, 09:34:55 PM »

hey guys i had a chance to test it today. same spot same weather. now i would never say it added 5horse but the engine for sure pulls stronger than it did last weekend. pay no mind to the launch :glee: theres no swinger extensions so you just ride the clutch and try to keep it going straight

[video=youtube;0cJMdUWo4AY]https://www.youtube.com/watch?v=0cJMdUWo4AY&feature=youtu.be[/video]

udontknowme · « **Reply #41 on:** August 09, 2014, 11:58:27 PM »

what do you make of this plug ? about 2/3 of it has 1.5mm ring then a small section is thicker lick 2.5mm. i wonder if thats from idling it to turn the bike around ? ive seen this before on other plugs where the ring isnt consistent in size all the way around but couldnt figure out what caused it. the burned part of the strap appears to be bewteen the red marks

[ATTACH=CONFIG]5899[/ATTACH]

[ATTACH=CONFIG]5900[/ATTACH]

[ATTACH=CONFIG]5901[/ATTACH]