RNBRAD Posted August 30, 2007 Report Share Posted August 30, 2007 If Pv's are pointless on a drag motor, then why do they put them on there? Quote Link to comment Share on other sites More sharing options...
dajogejr Posted August 30, 2007 Report Share Posted August 30, 2007 If Pv's are pointless on a drag motor, then why do they put them on there? Well..Brad...they are pointless on a drag motor...to a point. That's why most drag racers that use Cheetahs block them off, especially the bigger cheetahs. The real benefit of a Cheetah cylinder is the much larger intakes, bigger pistons and larger exhaust ports. The smaller Cheetahs, 10, 7, 4 and stock stroke used as duners are great for the power valve....but you're leaving the line in a drag race at 7 to 9K....the PV plays no part in that... Just my observation, and I go to the track with probably 10 guys with Cheetah motors.... Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 30, 2007 Report Share Posted August 30, 2007 Well..Brad...they are pointless on a drag motor...to a point.That's why most drag racers that use Cheetahs block them off, especially the bigger cheetahs. The real benefit of a Cheetah cylinder is the much larger intakes, bigger pistons and larger exhaust ports. The smaller Cheetahs, 10, 7, 4 and stock stroke used as duners are great for the power valve....but you're leaving the line in a drag race at 7 to 9K....the PV plays no part in that... Just my observation, and I go to the track with probably 10 guys with Cheetah motors.... Thanks Dave, I was being a little sarcastic though, but you proved my point. The PV's are there because they were not just intended as a "drag only" motor. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted August 30, 2007 Report Share Posted August 30, 2007 Gotcha...Sarcasm sometimes doesn't translate by being read on the screen often...LOL... To be honest, if money wasn't the object, I'd have a 4 mil cheetah with powervalve for my duner. Good blend of everything, power to have fun, win a few races...but bounce around the dunes too!! Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted August 30, 2007 Report Share Posted August 30, 2007 If Pv's are pointless on a drag motor, then why do they put them on there? Well for those that don Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 31, 2007 Report Share Posted August 31, 2007 Well for those that don Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted August 31, 2007 Report Share Posted August 31, 2007 (edited) So Calvin is adding a PV to a "drag" motor to add more bottom end? Why does a "drag" motor need a PV if it's obsolete in a drag race situation? BTW, what about the Trinity Sundahl banshee, wonder why they put a drag race motor in that thing? from motorhead: The bike is powered by Trinity Racing 400cc Cheetah motor kit with V-Force Reeds, Stage IV pipes and silencers, a Trinity sure shift and a Trinity heavy clutch kit. The bike is the best even off the very bottom of the power band. the "The bike is the best even off the very bottom of the power band. " is why they use it. Racing the baja they are in and out of corners shifting up and down. they are not constantly wide open throttle. so to make up for that lack of bottom end, introduce the PV. what better motor then the Cheetah with a PV? its got balls to go wideopen and still has the bottom end they desire for the portions of the race that are not as "fast" as others. EDIT: sorry thats motorhelmets, not motorhead Edited August 31, 2007 by Bansh-eman Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 31, 2007 Report Share Posted August 31, 2007 Exactly my point, a Cheetah is a race motor than can be used for several things and cannot be considered as a drag only motor. If that was the case then they would never put a PV on a drag only motor. People use them from hill climbs, to circle track ice and dirt, pikes peak hill climb, duneing, cross country, Baja etc... on and on where a PV is a definite benefit. So there is a lot of people to question as why they didn't do their research and why they are using a "drag" motor to do other things. Reason is, it's not just a drag motor, it does great in many other applications as well, period. To me that's almost the same as saying a drag pipe is only good for drag racing, not true as well. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted August 31, 2007 Report Share Posted August 31, 2007 If I"m not mistaken...the bigger Cheetah are welded or blocked off powervalves...14 and bigger, I think...not 100% sure of that. Anyone that tries to make anything bigger than a 10 mil into a duner should probably have their head checked, anywho....LOL.. Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted August 31, 2007 Report Share Posted August 31, 2007 the motors design is still that of a drag motor. the size of the intake and exhaust ports, the transfers everything is a drag design with a PV slapped on there.. Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted September 1, 2007 Report Share Posted September 1, 2007 Your just confusing the term drag with race. It is of a racing design which is exactly how it's marketed. It still needs work to have complete drag racing port specs. They are marketed as race because this covers a lot of different things the cylinders were intended for. If you don't believe me, just look around, don't let me be the only one to tell you a 421 Cheetah, cub or whatever is not just a drag only engine and also make killer dune motors among other things. Now if you take your Cheetah 421 PV, block off the PV's and put it on alky, full race porting, straight cuts, override, dual 39's, drag pipes, 12+ over swinger, guess what? you just made your quad for dragging only. Now if you take the same motor with Trinity pipes, dual 35's, +4 swinger, and timing advance. I don't think any amount of mods to stock cylinders could create a better dune motor. Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted September 1, 2007 Report Share Posted September 1, 2007 (edited) an rz350 topend with those mods would be more suited for duning before a cheetah 421. i dont know what you consider a "good" duner but that 421 is too much to handle for simply pissing around in the dunes all the time. your working the bike more then having fun. Edited September 1, 2007 by Bansh-eman Quote Link to comment Share on other sites More sharing options...
dajogejr Posted September 1, 2007 Report Share Posted September 1, 2007 It still needs work to have complete drag racing port specs. I would bet most builders would disagree with that statement. Any motor that comes out of CP has drag race port timings. Once you get into porting specs..(which,..I don't know what they are, just saying) such as port timing, blowdown, etc., most builders have a range on that in which the call those figures drag porting. Now...will one builder agree with another on the exact number....no. A range...yep. I can appreciate what both of you are saying. You're kind of arguing two different points. Yes....it is designed as a drag motor, then enhanced with a powervalve to be more well rounded. Again...on bigger Cheetah you won't find a power valve, it's blocked off. Which brings me to my next point.... I"m looking into either buying a 20 mil Cheetah or an 18mil DM cylinder for next year. Can I still trail ride with these motors? :yelrotflmao: :yelrotflmao: :yelrotflmao: :yelrotflmao: Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted September 1, 2007 Report Share Posted September 1, 2007 Dave if you check with the big names, like Ohton, RDZ, K&T, and even Jeff and Jim etc... I think Ohton has 3 levels of porting for the cubs and stage 3 is full drag race porting. I'm sure it is subjective as to what port specs necisitates "drag porting". These guys may just be out to make a buck or two but they are porting the piss out of all these engines on the drag motors they build. So when most of them have on their website "Full drag porting, or stage 3 etc.. So to most builders as I see it, they are porting them for drag, to me they are not a complete drag port. Some builders may feel that the stock specs are a complete drag port, but I don't know of any cause every builder that builds one for drag racing is porting them. They've been doing it since they 1st came out and most of them are charging around 400 for their drag porting. A good duner to me would be any stock stroke to 4mm cub, 400 or 421 cheetah. I have not rode a 421 but have rode a 400 with pv's. If I had it to do all over again I would have it or the 421 with pv's over the 421 cub. Different strokes for different folks, some people ride scooters some ride race bikes. An RD350 wouldn't be bad for the bottom end provided by the PV, but I would be missing the top end pretty quick. I've ridden just about every combo of stock jugg banshee to 4 mil different ports, yada yada on and on and by far the best motor's I've ridden for dunes is the 421cub and 400 cheetah. I'll putt around dunes all day on my cub and enjoy it way more than any combo I ever had with my stock motor. Quote Link to comment Share on other sites More sharing options...
ClimbAnyHill Posted September 1, 2007 Report Share Posted September 1, 2007 I saw that bike on there a couple months back. Bike is two miles from me... Ridiculous price!! Quote Link to comment Share on other sites More sharing options...
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