SXR dasa powervalve fuel consumption. How bad is it on the sxr800.

I am hoping someone can give me an idea of how much more fuel a dasa powervalve motor will use. I'm looking at using this setup with a fp wet pipe and stock carbs but don't want terrible milage.
 

Matt_E

steals hub caps from cars
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More power = more fuel.
That power has to come from somewhere and it's particularly bad when moving a heavy pig like the SXR.
 
Probably not gonna be real happy with the stock 40's (38's) when you upgrade. Are you stroking or boring? My Group K 800 had Sudco 42's and used more fuel than a stocker but not much. Kommander 849 with duel mikuni 46's used a lot more. DASA 4mm stroker I'm running now with Novi 48's uses about a 3rd more than stock when running it hard. Definately gonna want more "carb", those GRS 48's that are for sale would be the ticket. Used to run BN GRS carbs back in the day and they worked awesome. I'll be in Bullhead city in a few weeks if you want to try out the setup. Running FPP wet pipe also. Like Matt said more power more fuel.
 
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Honestly, i have the novi 48's with a 875cc dasa kawi, dry pipe on my pig and it's not any worse then the stock motor with dry pipe and 40s. All I know is if you go with the dry pipe be prepared to suck some gas. Not sure about the wet pipe, but I am sure the piston speed is up there. I think if your bore to stroke ratio is higher it actually runs more efficiently, not sure though. Here is a link to some wikipedia info, this stuff gets confusing so the experts are the ones who would know. Keep in mind you will have fun with figuring out jetting, pump, and prop size. It's been a painful summer for me, but I am finally where I need to be.

https://en.wikipedia.org/wiki/Stroke_ratio

I am new to a lot of this stuff so I am sure the guys that have been around longer would know for sure.

dasa 875cc.jpg
 
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Basically, if you put a pipe on any motor it's going to drink more due to piston speed. If you want good economy, Super Jet is the way to go. A 701 with a wet pipe and 38's is perfect for for rec. Mine (Dasa 875cc) drinks 7 gallons to my buddies 5 gallons (similar Super Jet set up). I usually try to avoid long term top end use and use more mid to top. Sorry to be so bold, but I am just trying to be honest. In the end, if you go with the Dasa you'll be happy once it's tuned in, but it will drink more fuel then your stock set up. I hope this helps, Dave.
 
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djkorn1

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Kawi is heavier = more fuel. I noticed when I got my light hull, fuel consumption went WAY WAY WAY down. Instead of going big motor, go light hull. More reliable, HUGE power gain, less fuel consumption, and more fun to ride.
 
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The Dasa is so much fun though! I was loving it today, crazy chop and a lot of boat traffic on Lake Minnetonka today! I must say your EVO hull is really cool boat, good to know that it is better on fuel. A PV motor would be sweet in that thing, but sure stock motor rips does the job.
 
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The hardest part of the motor is if you have no starting point (stock set up) and all the specs seem to vary, so tuning can be difficult.

I started 150m 14 0 p 115g spring 2.5 n/s and 60 return from manufacturer on the 48's. I am now at 127.5 m and at 122.5 p same everywhere else (painful process). I also had the advance plate, and I unplugged the temp sensor, and had a jetnetics charging flywheel (must be advanced) I was way to advanced and created some of my issues. I ended up getting a advent and going back to stock flywheel and life was good after that.

I was super disappointed at first, but the jetting was way off for my set up and my timing was way to advanced (my own fault). Also, went from a 14/18 (140mm) to a 13/22.5 140mm) and that made a huge difference. I kind of abandoned the single carb set up, because the fuel consumption on the 48's wasn't much worse. I am sure if you hold it wide open all the time the 48's would be a different story. I am new to all this stuff, so that is probably why it has been a struggle. I can say I did most of it on my own, and the "Dasa list your specs" post helped out a ton!
 
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I forgot to mention low end, it seems good to me. I am sure that has a lot to do with prop set up. The 13 seem to launch off waves way better then the 14 and the motor real hard around 4500rpm - 7000rpm (just a guess). Keep in mind I am running dry pipe, hope that gives you an idea. I can imagine in your hull and a good pump, low end would be a lot better.
 
Mine was already setup. I have been changing wet pipe screws a little,but really want to dry pipe it. I also think I need to break down a get a mag pump. 623 how did you mount your dry pipe with the DASA cylinder? Fab up new brakets?
 
My 4mm stroke Judge ported 862 Dasa runs like a raped ape with Novi48s on an R&D Sidedraft , Wetpipe with C4 chamber , advent T4 total loss , race gas . It sat most of the summer while I rode dasa powered superjet . Just now getting it back out and riding it . Running 140 mag pump and plan on having it bored to 145mm . Also getting a set of domes machined to lower compression . This thing will chew up $75 in race gas before you know it . Heavy hull with lots of drag leads to lots of full throttle riding
 
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The SS factory pipe brackets should work on the Dasa head. I like the dry pipe, but I like to get some speed going when I ride on the lakes with heavy boat traffic.

Legdragger sounds like yours is rocking, nice to hear! I'm gonna enjoy the holiday today by burning some fuel and hits some waves! Happy Labor day all, or should I say happy riding day (my labor), Dave.
 
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