I tuned a bone stock 2003 X440 motorcycle yesterday at the dyno. We had only gotten 37HP with a mildly ported 450cc ATK built motor previously. Within 5 hours of the last dyno session the ATK motor took a dump (what a surprise from the leaders in Cannondale design)! Seems that when ATK had the latest 96.5mm piston kits made up a while back they forgot that they were using a steel liner instead on an aluminum one. The clearances are way too tight and the motor seized with very little time.
Well I rebuilt this one a while back and it has more than 5 hours on it now. I have been begging this guy to dyno tune it since I rebuilt it. Well we finally did saturday. We got 41hp and a flat AFR line. We probably lost some power (on both runs ATK motor and yesterday) as we used a worn knobby to dyno with. But we did use the same tire both times.
[attachment=9829:X440_Dyno_Day.jpg]
Bone Stock X440 Motorcycle
QUOTE (NRath @ Jan 18 2010, 12:09 PM) <{POST_SNAPBACK}>
Is that the fuel pump mounted under the radiator? I hope I'm wrong otherwise I'm thinking there really couldn't be much worse of a place to put it!
But, otherwise the dyno # is pretty good for a stocker! I'm guessing the gains over 37 come from the exhaust.
But, otherwise the dyno # is pretty good for a stocker! I'm guessing the gains over 37 come from the exhaust.
Neil,
That is the stock mounting location on the later model bikes. The gains were from a properly built motor. The motors were identical except I used the ASSO piston kit. The exhaust is stock as well.
I was comparing the hp # to the original claim for the quads. Got to figure those motors were well built in the beginning, as well. That one probably benefitted from some extra tuning and the m/c pipe. That pipe is wide open compared to what came stock on the quads. Nice, long split header, too. And, the m/c horn was good for +1 over 37.
All that in mind, what did they actually rate the motorcycles at? I can't believe it would be 37.
All that in mind, what did they actually rate the motorcycles at? I can't believe it would be 37.
This is the 3rd motor for this guy in the same bike. The first motor was the stocker, the second one was an updated 450cc ported ATK motor (that I dynoed and tried to tune) and piston siezed with less than 5 hours on it, and lastly the motor I built for him. When he came to me, he only wanted to rebuild it cheaply and sell the bike. When I told him about the crank problem I thought I was going to lose him, but he hung in there and did a complete stock rebuild (432cc). He is so happy with the bike he doesn't want to sell it anymore and he is in fact looking to add some more power now. He has a lot of money in this project, I told him to enjoy it for a while without spending any more $. I did beg him to dyno it after I rebuilt it just to tune it, because he likes to drag race with it. It had more hours on it when we dynoed it then the last ATK motor had total!
There is not much performance gains on the bike vs the quad (stock). I would rate the Moto/Blaze a little higher in performance initially. The airbox design on the bikes sucks and the exhaust is not that much better, especially against the Ti pipe. I have always wanted to do a stone stock dyno run and this is as close as it gets. It does have some clean up porting done, but it's pretty minor.
There is not much performance gains on the bike vs the quad (stock). I would rate the Moto/Blaze a little higher in performance initially. The airbox design on the bikes sucks and the exhaust is not that much better, especially against the Ti pipe. I have always wanted to do a stone stock dyno run and this is as close as it gets. It does have some clean up porting done, but it's pretty minor.
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Gibson265R
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I feel that 37hp or even 41hp is low..especially for a dirt bike. My cannibal before any porting or any mods with the exception of an HMF slip on produced 38hp. It now produces over 48hp with porting (still 432cc). In my opinion, a dirt bike should be anywhere from 5-10 more hp over an atv of the same engine size. The ported 450 should be pushing out even more. I would expect to be in the mid 50's if i bumped up to the 450 mark...
QUOTE (Gibson265R @ Jan 30 2010, 02:02 AM) <{POST_SNAPBACK}>
I feel that 37hp or even 41hp is low..especially for a dirt bike. My cannibal before any porting or any mods with the exception of an HMF slip on produced 38hp. It now produces over 48hp with porting (still 432cc). In my opinion, a dirt bike should be anywhere from 5-10 more hp over an atv of the same engine size. The ported 450 should be pushing out even more. I would expect to be in the mid 50's if i bumped up to the 450 mark...
This is hard to directly compare unless you took your quad to the same dyno as he did the dirt bike on and did it on the same day. Also, remember he was using the knobby tire, stock airbox etc. I'm not sure what you mean about expecting the 5-10 more hp over a quad. It is the same motor. If you took your motor out of your quad and put it in his bike, do you think it would make 5-10 more hp just becuase it is in a bike frame?
A heavily ported 450 will put out mid 50's, but I don't know about mildly ported. I doubt it. My stock atk 450 quad motor put out 39 I think when it was brand new, now with heavy porting and opening up intake and exhaust we (c27) got 54. But that wasn't on the same dyno, so its really a mute point whether it was 37 38 or 39 hp, you know what I mean? The 39 was the baseline for mine.
The main point here seems to be the properly rebuilt and tuned 432 puts out 4 hp more than the previous 450 rebuilt by ATK. Kdeal, is that about right?
QUOTE (Gibson265R @ Jan 30 2010, 02:02 AM) <{POST_SNAPBACK}>
I feel that 37hp or even 41hp is low..especially for a dirt bike. My cannibal before any porting or any mods with the exception of an HMF slip on produced 38hp. It now produces over 48hp with porting (still 432cc). In my opinion, a dirt bike should be anywhere from 5-10 more hp over an atv of the same engine size. The ported 450 should be pushing out even more. I would expect to be in the mid 50's if i bumped up to the 450 mark...
The big killers on the bikes are the intakes and exhausts. I got 39 out of my bone stock 440S. I threw a 505 in it that pulled 58hp in my quad I got 56 in the tard. The tard was running a quiet core exhaust and a stock airbox with a ported bike stack. Im sure if it had duals on it which it will for this year and a modified airbox it would have been right there with the quad and possibly a few more. I will redyno without a quiet exhaust next time as since we found a track to ride. As far as gaining power on the dyno from using a bike tire verses quad road tires I have not seen a difference . I really dont understand the intake design of the bikes being so bizzare ,restictive and complicated,since they designed the engine for the bike specifically.
Of course if you look at it this way a bike with a stock motor pulls like a quad with a huge race engine.
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Gibson265R
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I was only saying that USUALLY you lose about 5-10 hp if you put a bike motor in a quad frame...example...YZ426/450 into a laeger/walsh/whatever 250r chassis. The bike motor will most definately lose about 7 hp when installed into the ATV chassis due to the extra drive train components. I have never seen the intake for the Dale motorcycle so that could be a huge limiting factor, judging by what Wistech stated. Anyway, in theory, a 50hp quad motor should be easily putting down 55hp in the bike...if intake and exhaust are similar.