Hey guys, I've had my hawk for about a year, and I found a guy that has a set of Wiseco 3mm pistons. It's the entire kit, two pistons, two sets of rings, two sets of c-clips, two pistons pins, and the gasket sets.
Even though I've worked with more than my share of car engines, I'm new to bike engines; so I have a couple questions. My questions are, how much is this kit worth? Who has better pistons - Wiseco or Arias?
The Wiseco are fine provided you rebalance the crank, otherwise vibration is a concern. You also have to relieve the cylinder sleeves a little bit with the 82mm pistons or the opposing piston skirt will hit the sleeve at BDC.
I have 82mm lightweight pistons available that weigh only about 5-7g more than stock pistons. $325/set including rings/gaskets/pins/clips. I also have cylinders bored and ready to go, for $80/pr., all you have to do is provide a good core set of cylinders in exhange.
Maybe they change the design over the years, but I had 82mm Wiseco's in my Hawk with no modification to the crank or cylinders other than the bore, ran the snot out of it, and never had a problem. I didn't bother to weigh them either
The dome and skirt design hasn't changed, (despite my pleas to re-do it completely) the base forging has a little bit but it hasn't altered the weight significantly. A complete Wiseco 82mm assy. comes in around 390g. Stock Honda assy is in the range of 345-350. My lightweights are around 355g. The Wisecos will work ok out of the box and there are plenty running around out there just that way, but at +40g over stock it isn't doing your crank any favors.
The power increase depends entirely what spec your engine is. Just dropping in a set of pistons with the rest of the engine stock, you'll get about 3-4hp peak but bags more midrange. When you add cams and head work/bigger valves, then power starts to go thru the roof. There are a lot of 700 dyno charts on my site, just click on the banner below.
The compression ratio works out to slightly less than 11:1. Stock is about 9:1. The heads can be skimmed .020" to .040" to bump it up higher if you want. My personal Hawk is close to 13:1.
Depends which 700 chart you are looking at I guess. 700/mild cams/stage 1 heads, yeah, that'll make about the same as stock SV power, ~67hp, the curves are fairly similar.
... Just dropping in a set of pistons with the rest of the engine stock, you'll get about 3-4hp peak but bags more midrange. When you add cams and head work/bigger valves, then power starts to go thru the roof.
I've been thinking/wondering about that. I'm wanting something I can ride around on the streets, and when there is good weather, take over to the old Indy Track and see what kind of times I can get. What setup do you think would be good for this?
The one shown in the chart has 700 lightweight pistons, cams, stg. 1 cylinder head porting, Factory 3.0 jet kit, Uni pods, M4 pipe. Valves seats are freshened up, all seals/orings/seal washers/gaskets etc are brand new from the base gaskets up, cams are timed using slotted sprockets, etc etc. For the engine stuff it's about $1500 installed. If you need the pipe/pods/jet kit/etc that is extra, obviously.