Having owned a Karpiel Disco Volante for over a year now, I feel that I have gone through enough to write a thorough review. A little background on my frame: it is a warranty frame, and has mismatched parts. The front/main triangle is a 99, the rear swingarm is the latest one, the lower linkage plates I believe are the older ones, and the upper linkage plates are from an Armageddon. So essentially, I don't really have a Disco, but close enough for me to give my opinion on the frame itself.
First off,
build quality. This frame is probably one of the strongest built frames on the market. I have high doubts that it will break. The main triangle and the swingarm are beef, and I believe the newer frames are cosmetically better looking, if not strengthened in some places. However, there are still some minor faults. The linkage plates are the weakest pieces on the frame. I've heard of these cracking, and I actually just found a crack in my lower linkage plate while I was taking apart my frame. I will post a picture soon for reference. I'm not certain how it was cracked, but I'm guessing I could have had a rock fly up and smack it hard enough? In my eyes, it's a beautiful frame. So strong, yet light enough to easily make a full build in the lower 40 pound range. Jan's frames measure on the smaller side. Mine is a small, but in comparison to other DH frames, I've found that it is tiny compared to other "small" sized frames.
Performance. Karpiel frames are all extremely plush! Or at least, this seems to be the nature of the Disco and Army. I can only assume that the Apocalypse (Karpiel's largest-travel frame) is the same. The down side, you're going to be bobbing a ton when pedaling uphill. You can pedal in a certain manner that seems to minimize the bobbing, so I can't say that it's too bad. When going down, the bike is awesome. The rear soaks up everything in it's path, and more. The frames should have a range of adjustability in travel, from 7-9", which is dialed in by twisting the circular piece on the upper linkage plate. I will post later on the settings for travel. There is one small bug with the suspension. I've noticed upon full compression, the wheel base of the Karpiel changes distinctively. Has this ever bothered me on the trail? No, at least not yet. But it's something to keep in mind.
Customer Service. What can I say? Karpiel lacks in the customer service department, or rather, there really is none. Especially now that the whereabouts of Jan Karpiel are unknown, I can't really say much for him. He is a very hard person to deal with, nice over the phone, but his mind is always in another place. He will tell you one thing, but mean something totally different. It seems that it is almost impossible to even get through to his head. I doubt he even knows of the troubles that I've been having, even though I have called him many times.
Maintenance. Having never owned another downhill frame, I can only say little about maintenance. But this is no single pivot, that is for sure. The bearings on the linkage plates need constant checking. After a year of riding, mine are shot. Check the linkage plates for cracks. Also check the bolts on the linkage plates, and make sure those are always tight. Lock-tite them with if needed.
Major faults. The Karpiel has a very finicky chain line. It requires a 118 spindle length bottom bracket. It has no ISCG mounts on the frame. But when it comes to chain guide choice, here is where you will run into problems. I have tried the Mr. Dirt, a MRP System 1, and an Evil SRS. Only the MRP System 1 and System 2 are known to work on the Karpiel, with the exception of a modified SRS. I'm a little uncertain as to what it takes to get the Evil guide to work, but I think Evil puts out something called the Supercharger? As for the MRPs, a System 1 HAS A LIMIT ON WHAT SIZE CHAINRING YOU SHOULD RUN. You can fit a 38, but you're cutting it close to rubbing the swing arm. I have a huge gash on mine ever since I knocked my MRP bash plate out of whack. I would run a 36 tooth chainring max. The MRP System 2 is probably the best bet for the Karpiel, but even then, it also needs modifications to make it work properly. The guys at go-ride.com do put out a bolt on kit for the System 2, so it is all ready for installation right out of the box.
My Personal Ratings. The Karpiel is a wonderful frame. There are quite a few quirks to be worked out about it, but other than that, I've loved the way mine rides. It requires much attention. If the backbone of the company were stable, I think Karpiel would have a much better reputation. I'd only give it a 6/10, because of the lack of customer service, which plays a major role in purchasing and owning a bike frame. If soley based on performance, build, and the little quirks of the frame itself, I'd say around 8-9. Would I buy another? Well, seeing as how the company might not even be around anymore, I guess that's not much of an option. I do like the way the bike rides, and how it has held up to my hack-riding. But I have seen way too much down time for me to really have the piece of mind to deal with this type of hassle again.