kawiking Posted May 7, 2007 Author Report Posted May 7, 2007 it was weird,buddy got his fundy 730 motor for his praire 700 in acouple of days before we left. fundy put it on his motos dyno and it pulled 102 at the crank. buddy put it on dyno at l.s. and pulled 46 at the wheels .not a happy camper. my buddies bike had 55 and its just like mine except i have the 34 carbs ,porting and cpi out of frames(i did have) and pulled 53 . thats what freaked me out, guys inside the store said they could hear mine was way rich. i just wanted to problem solve it,my bikes faster than his and we all new it .he said the 4 mills timing was killing it. it has a dyna cdi on it,told him to put the timing plate on instead... Quote
dajogejr Posted May 7, 2007 Report Posted May 7, 2007 it was weird,buddy got his fundy 730 motor for his praire 700 in acouple of days before we left. fundy put it on his motos dyno and it pulled 102 at the crank. buddy put it on dyno at l.s. and pulled 46 at the wheels .not a happy camper. my buddies bike had 55 and its just like mine except i have the 34 carbs ,porting and cpi out of frames(i did have) and pulled 53 . thats what freaked me out, guys inside the store said they could hear mine was way rich. i just wanted to problem solve it,my bikes faster than his and we all new it .he said the 4 mills timing was killing it. it has a dyna cdi on it,told him to put the timing plate on instead... Go somewhere else. I used a plate (still am) and a Dyna on my 4 mil cub on gas. It ripped...and I guarantee is was at or near 100HP at the rear wheels. Quote
FireHead Posted May 7, 2007 Report Posted May 7, 2007 Well, rear wheel dynos are not accurate at all. They are only good for tuning and telling you if your bike makes more hp and torque than somebody elses on the same dyno. Only way to really check an engine for hp and torque accurately is on a crank dyno. Every rear wheel dyno can be different, and even daily weather conditions can change the readings also. I am going to slightly disagree with you. However, I do agree withyou that the recent fashion trend of dyno'ing your bike to show your buddy is a bit annoying. Oh well, maybe Paris Hilton will do it and it won't be cool anymore. Most inertia brake chassis dyno's are garbage, but an AC, eddy current, or water brake chassis dyno can be a very accurate tool. An engine dyno and a chassis dyno are meant to be used differently, but both are are generally very accurate is the torque absorber and instrumentation are above a certain level of sophistication. Quote
dajogejr Posted May 7, 2007 Report Posted May 7, 2007 maybe Paris Hilton will do it and it won't be cool anymore. She won't be doing that anytime soon...unless they put one in her cell. (Stupid biyatch...ha ha...) :whistling: Quote
Snopczynski Posted May 7, 2007 Report Posted May 7, 2007 Isn't that the point of an SAE corrected dyno number to take into consideration changes in temp, humidity, etc.? (Not trying to be a smart ass...don't take it that way...honest.) I agree...crank dyno is way more accurate. But...it is nice knowing how much HP is being put to the rear wheels, too... Well the number you get off the chassis dyno is a formulated crank hp number. Dynojet even had a press release a while ago to say the formula is not accurate. Quote
dajogejr Posted May 7, 2007 Report Posted May 7, 2007 Hmmm...that one I've never heard. But...it does make sense, if that's what it's trying to do. There's no way any program can "Guess" HP based on all the different gearing, tire combos, etc that are out there...which will play a heavy roll in a dyno number. This is interesting...any one else care to comment on that. I thought a dynojet measured rear wheel HP...not an estimated crank number... Mark...what say you? Quote
locogato11283 Posted May 7, 2007 Report Posted May 7, 2007 i say fuck dynos altogether and i say fuck paris hilton in the butt!! :biggrin: Quote
FireHead Posted May 8, 2007 Report Posted May 8, 2007 Hmmm...that one I've never heard. But...it does make sense, if that's what it's trying to do.There's no way any program can "Guess" HP based on all the different gearing, tire combos, etc that are out there...which will play a heavy roll in a dyno number. This is interesting...any one else care to comment on that. I thought a dynojet measured rear wheel HP...not an estimated crank number... Mark...what say you? Mark says that if adyno I'd properly instrumented than you could calculate the speed at which Loco's dick falls off after nailing Paris Hilton. On a slightly more serious note. On a chassis dyno, engine horsepower is a calculated number, but itis still pretty accurate (within a couple tenths of apercent assuming you good measuringequipment). Engine horsepower is the last thing you are looking at on a chassis dyno anyway. Quote
Justintoxicated Posted May 8, 2007 Report Posted May 8, 2007 I went from FMF Fattys to CPI Big Bores (I don't have enough motor for the big bore inframes either!) I still saw a noticable improvement when shooting the hill. I have the 12-port and I'm not even drag ported. Something is up... Quote
kawiking Posted August 6, 2007 Author Report Posted August 6, 2007 well im bringing this old post back up. sorry--lol !! ive decidied to put a k&t head with 17 domes on my shee.. as stated before not good luck with my out of frames,put my old fmf's back on and ran better. well i have a drag port done on stock cyln and im sure the fmfs arent the best for it on top end. im wondering if i should go ahead and get inframe drag pipes are toomey's.... the cpi out of frames i have are on their third owner. i got them from a frienf,he said they were small bores..... as stated at begaining of thread...my motor did not like them !!!! is there any way to tell if they are a big/small bore ??? my compression is about 140 ish with my drag port.... thats why im going with the 17' domes (i know race gas....) do you thinkl the added compression will be enough for drag pipes ?? Quote
Snopczynski Posted August 6, 2007 Report Posted August 6, 2007 So what are you unhappy with from the Dyno then? Quote
kawiking Posted August 6, 2007 Author Report Posted August 6, 2007 no no... this isnt about the dyno run..sorry.. this is about me going to a 17 dome and wondering if i should go with a cpi/shear drag pipe or go with a toomey ?? i really wish i could put my cpi's out of frames back on. the whole thing with them was..... they felt strong till the top end. then they felt rich--- it wouldnt fall on its face but it wouldnt pull hard. my port job is mostley top end so it was hurting me,put it on dyno and everybody said way to rich..dropped mains and still cut out some on top. buddy said pipes were small bores--others say it acted like i had big bores.he used to run them and said they ran good,when he had them the tips were broke off(stingers).. i had some pipe welded on for tips. Quote
Snopczynski Posted October 26, 2007 Report Posted October 26, 2007 Even on the dyno, the jetting wont get perfect. Jet it off feel and observation under real world load out in the sand or wherever your riding it. If going down with mains doesn't help, then go up. Remember, needle taper towards the end is also gonna help you get into the top end. If its not the right needle or the taper is wrong. Well then you need to get that adjusted as well. Quote
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