Thack82

I hope I'm lucky enough to meet you face to face someday. I bet you everything I own you wouldn't say this bull shit to my face. If you did I would stomp a mud hole in your ass and walk it dry. I can guarantee you that.

Your assumption is wrong, I drink a little and don't don't partake in ANY drugs. I would appreciate it if you would keep your stupid comments and derogatory remarks to your self. Your worse than a little kid, but if your going to assume things about me and write them I'll tell you what I assume about you. I'm assuming your a ass hole that probably doesn't even own a Banshee and if you do it's a stock cylinder rag with a set of T5's, a jet kit, and a extended stock style swingarm and you think you've got yourself a bad ass "Drag Bike". So your idea of a good time is logging on HQ and spewing bullshit and trash talking in a attempt to make yourself feel like your a big deal. Please do me and everybody else a favor and shut the fuck up.

What's worse than meth and heroin dick weed? You and Zilla must be brothers.

Your right I should have seen it coming. I know you guys don't believe this but I do try to help out anybody I can and I guess Tom saw that and set out to take advantage of me and take me for everything he possibly could. I've been a huge fan and believer in the OG Rockets and the R2's and I still am. When I decided to build and go all out on a 10 mil trail motor Tom was the first person I called. I wanted to get Tom to commit to building me a set of BB PV Rocket Inframes before I committed to building the 10 mil Cheetah. I just wanted to prevent him from screwing anybody else over if I could.

I'm sure a lot of you guys have already heard about the mess I got into with Tom Borrink when I hired him to build me a set of custom BB PV R2 Rocket Pipes for a 10 mil PV Cheetah that I had built, but I wanted to post a thread up on here so everybody knows to stay clear of him and WHATEVER YOU DO DON'T SEND HIM ANY MONEY, TOOLS, PARTS, OR ANYTHING ELSE THAT HAS ANY MONETARY VALUE!!! (1) I paid him $950 to design and build me one set of bare finish hydroformed pipes that matched my new 535cc Cheetah. (2) Then he started giving me a line of shit about his tug welder burning up on him and not having a set of sheet metal sheers and a bunch of other tooling that was required in order to build my pipes that he no longer had because he lost them when he split with his last ex-wife. ~ I told him to send me the links to sheers and other tooling he needed and I'd order it and have it shipped to him and boxed up my BRAND NEW Lincoln Tig Welder and shipped it to him so he could use it until he got his tig welder fixed or bought a new one. I told him; as far as the new tooling I bought was concerned he could pay me back a little at a time as he got the money. (3) A month or so passed by and I got a call from him saying he had contacted his Brother (Ron Borrink, the guy that actually designed and developed the Original Rocket Pipes "R1's" and R2's back in the day) and the designs and cut outs were finished........ but he was in between jobs and he didn't have the money to purchase the materials, welding gas, etc ($400 worth of shit) he needed to build my pipes but if I'd loan him the money he'd get it back to me in a few weeks. ~ So I sent him $400 to cover the materials and gas. The next thing I know he calls me up and tells me he's moving to Kentucky and he's designed two new versions of Banshee Pipes and a YFZ-450R Exhaust Systems and he's going back into the pipe building business and he wants me to be a 50% partner, but he needs to barrow my Duramax Pick-Up to move the camper he's going to live in temporarily until his new house and shop is built and he needs to use my shop temporarily to build pipes in until his is done. ~ At this point I must have been gluten for punishment because l loaned him my truck and he destroyed the transfer case in it, parked the camper on my property so him along with his in-laws and wife would have a place to live until his pipe business was back in full swing. Anyway to make a long story short he leached off me for three months, then broke in my shop and stole about 10k worth of tools and hooked to his piece of shit camper and headed to Tennessee. Since my incounter with him I've found out he has done this to a bunch of people before and after me and he's addicted to meth and heroin. Stay away from this piece of shit, don't let him take you like he took me.

It was my understanding that the bigger 72mm Super Cubs and Super Serval's encountered some head gasket issues that were attributed to domes not being machined properly when they first introduced just like McDurmott had with the Cheetah. The Cheetah was/is designed and manufactured by Calvin at CP Industries just like the Cub, Serval, DM Cheetah, ect. McDurmott just bought the exclusive rights to that particular setup believing it had the means to be the ultimate power plant for a Banshee. I think he put the Cheetah on the market before they had all the issues figured out and that combined with a lack of knowledge on power valve exhaust port porting characteristics, and the fact that none of the exhaust builders had developed a set of pipes to work with and compliment a power valve engine all came together to create the Cheetah's demise. If you step back and look at everything the Cheetah offers it has to fall back on those three things. What features and design characteristics does the Cheetah have that make it less desirable than a Super Cub or Super Serval other than overall cost? The bigger six bolt 250R intakes can't be a bad thing because the intake issues that have limited and plagued the 521cc+ Super Cub and Super Serval has been well documented since their release. The Cheetah is a 26 port Mono-Cylinder with the same or very similar to the port timings CP used on their DM Cheetah that's been a proven performer in the Banshee racing world since its debut, and the exhaust driven "Rotax Style" Power Valve's have been used and proven to be effective and offer a distinct advantage over non-power valved two stroke power plants that were used in Snowmobiles and PWC's for years until the production of two stroke engines was brought to a stop by the EPA do to their inability to meet the current US emission laws. So the way I look at is the problem has to lie with the additional cost associated with building the Cheetah and the three issues I mentioned previously. If you overlook the additional cost associated with building a Cheetah and get a new untouched set of Cheetah Cylinder's in the hands of a capable builder that's knowledgeable on the mechanics of a two stroke power valve engine equipped with that particular type of power valve there is no reason the Cheetah can't be capable of being the top performers as long as it's equipped with the right set of big bore pipes that are designed to complement a engine that has variable exhaust port timing. Those are the things I took into consideration when I decided to build a bullet proof 10 mil trail motor. I was deciding between the 535cc Cheetah and the 521cc Super Serval and I decided the Cheetah was the best option for me and what I was trying to accomplish with my bike.

My Cheetah uses the Trinity Billet Power Valves Trick. I was refuting to them as Rotax Style because they are driven by the exhaust pressure generated by the engine during the combustion process VS a mechanical power valves that are driven by centrifugal weights and spring pressure that are attached to a internal linkage that's driven by the crankshaft, or a servo motor that's controlled by the ignition. I can see how that could have been confusing because the exhaust pressure has to overcome tension created by a spring and the billet power valves that my Cheetah has to overcome a metered portion of the exhaust flow. I apologize for the confusion. I don't see any reason why actual Rotax Power Valves couldn't be used on the Cheetah, all that you'd need to do is have the Rotax Power Valve Slides machinined to match the Trinity Power Valve Slides. As far as I know the Rotax version would bolt up on the Cheetah Cylinder's without any other modifications.

We need to get together and ride sometime. I live in central Kentucky. Where are you from?

Your absolutely right n20fast, Trinity didn't help matters for sure. They didnt even off the right components to compliment the Cheetah platform. I'm not taking anything away from the Super Serval Ragun, it's a awesome motor. I just feel like the PV Cheetah doesn't get the props it deserves. It has a bad wrap for several reasons one of them is the expense associated with building one. A PV Cheetah cost roughly 38% more to build cc for cc.

The way the power valves are fit and the way the exhaust port is ported and shaped is absolutely crucial on the PV Cheetah! I went with Kan because he was familiar with Rotax PV Engines what to do to make them run but he wasn't cheap by any means. If you don't want to go with him I were you I'd talk to Arlene at LED or builder that's big in the PWC or Snowmobile World that builds Rotax PV Engines on a regular basis. IMO the PV Cheetah is capable of being the elite Banshee Power Plant, if you talk to the 250R guys that run the CP PV Sphinx Motors they absolutely LOVE them, but the Banshee guys hate them and talk shit about them all the time and we're talking about a twin cylinder version of the same engine essentially. I truly believe the right builder and combination of parts is what makes the difference and to be honest I think the right set of big bore pipes that were developed specifically for the Cheetah and Rotax Power Valves would be a game changer for the Cheetah guys. I've studied the Rotax Engines and the Pipes that are proven performers on them and the design characteristics on those pipes have are differ from a standard Banshee Pipes quit-a-bit. With the Rotax Engine you want the scavenging pulse waves to travel around the expansion chambers at the same or close to the same revolutions (RPM) that the engine is turning. Typically the pipes have longer neck with a small diameter that expands at a much slower rate, and the expansion chamber is shorter with a significantly bigger diameter. After doing a lot of research and reading Irealized the old school Rocket R2's had a lot in common with the successful Rotax Pipes. That's why I got with that toothless piece shit junky Tom Borrink. I thought he'd be the perfect guy to develop a Inframe PV Pipe for the PV Cheetah. I paid dearly for that mistake.

Your probably write on the spelling Trick, I can't spell for shit and my grammar and punctuation is so bad it almost comical. I think I talked to that guy via email a time or two but most of our conversations took place over the phone. I got the impression that this guy was probably in his mid 40's to mid 50's but I don't really know. I'm usually pretty good remembering names and faces. I hope Duncan gets back with me soon so I put some of this doubt others are expressing to rest. I appreciate your input and help with this more than you know.

The Rotax Style Power Valves on the 10 mil Cheetah are tuned using Keihin Carburetor Main Jet's. I can pretty much make it react anyway way I want it to based on the terrain I'm in. I'm running R2's and 38mm PWK Air Strikers on my motor. I had it built to run on 100LL/32:1 av-gas pre-mix, I can lug around in the tightest of trails with ease and run like a raped ape in the wide open river bottoms. What pipe and carb combo are you running with your 521 Super Serval?

My new 535 PV Cheetah has the big 6-Bolt 1989 Honda 250R Intake's. The Big Bore UPP Intakes they have available at this time don't have the cross-over tube ports. When I talked to Bill a few months back he said he would cast me a custom set of red BB Polyurethane Intakes with the cross-over tube ports when I was ready. I like the people at UPP and their products. Both are top notch.

I sent Duncan a email. You can see it bellow. I really don't know why it matters, do you think I'm lying about that? What do I stand to gain lying to everybody about someone I talked to at DRI that talked to me about PT Mid's and my power plant setup? I'll post up the reply that I get back from Duncan as soon as I get it.

I can see that being true.

I give you my word, the guy that helped me that I talked to was Curtis Duncan. I'll see if I can dig up a email where we discussed some of the issues I was having with the power dead lining and falling off very fast screen shot it and post it up so you can see it, or you can call the Duncan's tech support number and ask for Curtis. I think you ask me this a few years ago when it was brought up talking to him and getting him to help me. I wouldn't pull a bull shit name out of my ass and fabricate a story just to blow smile up your ass. I was having problems with that particular motor and setup being slow in a straight line drag race. A stock YFZ450 with a exhaust would be neck and neck with me. So I called Jeff at FAST because I baught the Serval Setup from him and he told me from the start that he didn't feel like the PT Mid's were the right pipe for that power plant and I needed to call or contact Duncan and get their input on that engine and pipe combination. So that's what I did. Curtis told me to try a few different sprocket combinations and make some timing changes on my digital ignition that helped out a lot but I still wasn't happy. The next time I called he told me I could find a set of pipes that would better with my particular engine setup. I talked to him briefly about the PT High Rev's and he said there were high rev pipes out there that would perform better on the Serval than the PT High Rev's so I started trying other pipe and carburetor combinations until I found a setup that that did what I wanted it to do.

I thought a boost bottle was useless piece of trash until I rode at Wind Rock OHV without one. I went to Wind Rock in Tennessee with a couple of buddy's on Z400's and 400EX's for a weekend. We unloaded our bikes at a elavation around 1,200ft and rode up the side of that mountain five hours straight and when we finally hit the peak we were just over 7,000ft. I actually trashed my stock cylinder top end on that ride. When I went back the next year I was running the Serval, DRI Masterflow Intake System with Boost Bottle, the Intel-A-Jet Fuel Induction System, and the Dynatek Digital Ignition and my bike made it through the entire weekend without any issues. I was able to adjust the main fuel circuit and digital timing curve periodically as the elevation increased. Those mods combined with the boost bottle determined if my bike was able to pull itself off the trailer under its own power or not when I got back home at 740ft above sea level. Wind Rock is brutal to say the least! It's by far the roughest most challenging terrain I've rode in to date. Ever trail we took was labeled 4X4 or wench required. It definitely helped me find any weak areas that I hadn't found yet or overlooked. I've got UPP talked into casting me a red set of Big Bore Polyurethane Intakes with the Boost Bottle Ports but I haven't taken the time to do all the math, design, and fabricate a boost bottle out of aluminum that matches all the specs on my new power plant. A group of professors at a college university in Belfast have done all the testing and developed a specific formula and guidelines that need to be used when building a boost bottle chamber to match a specific motor and carburetor setup that I plan on using. I'll start a thread and keep you guys informed and post up the test results and data when I from start to finish when I start that project.

He was the guy that helped me set up my old stock stroke Serval from Duncan Racing back when I ran the KORHS Series on my Banshee several years ago. I always assumed he was the owner or one of the owners of DRI but I don't know that sure.

Right, I'm not claiming the boost bottle aids any with horsepower gains although I did see some testing back about 6 years ago where a guy did with DRI's Master Flow Intake with boost bottle VS DRI's Billet Intakes that were separated that showed a 1. something peak horsepower gain with the Masterfow Intake System but I've searched for that testing relentlessly several times since then with no luck. I'm almost positive Curtis Duncan at Duncan Racing did that testing and sent me that data in a email but I haven't been able to find it. I either dreamed it or deleted the email because I can't find it.

I'd have one if UPP made a set of the big bore intakes that had the hook ups and a I could get my hands on a chamber that matched the engines displacement and the other specs on my motor. I like a boost bottle because it helps the engine aclamate to rapid changes in elevation over a short period of time. That and it helps hold the wiring harness, throttle cable, fuel lines, etc up away from the engine. I know most people think the boost bottle is joke and I'm a joke for promoting running one but they can be benifital in the right application. That technology was actually developed by Yamaha to solve a issue they were having with a old two stroke sled as it changed elavations. For a true recreational trail rider they do offer some benefits that make running one make sense. Let the hating begin. Lol

I don't know a lot about the riffleing mod for the actual banshee application but the guys that ran MX and Super Mini Dirt Bikes back in the day swore by the tapered riffle bore mod, but you know how strict the AMA rules are and the racers are looking for every little advantage they can get that will give them a head up on the competition. We're talking about the same guys that will spend $3,000 on a titanium bolt kits to save a few pounds. I looked into having my modified and upgraded 32mm Mikuni TM's Tapered and Riffle Bored to 35mm when I was concidering building a 4 mil 421 Serval. A standard +3mm Taper Bore was $30 per carb and a +3mm Tapered Riffle Bore was $85 per carb. If I had went the 4 mil Serval rout I would have gave the +3 Tapered Riffle Bores a shot but I took a beating on them and sold them to Mike Morgan (Zilla Guy) when I decided to build a 10 mil trail motor. Here's the 38mm Keihin PWK Air Strikers I'm running that have the Intel-A-Jet Fuel Induction System, Oversize Billet Fuel Bowls, Deep Well Sump Fuel Bowl Nuts, and few other mods that I'm running on my new 10 mil Cheetah.

I don't doubt that a bit Tyler, I'm sure your right. I was just thinking about his woods ridability and usable low end power. You've got a lot more experience with big striker motors than I do so you know more about the way these motors react to bigger carbs than I do. At one point in time I felt the same way about pipes. I thought a set of Hi Rev Inframe Drag Pipes would destroy usable lowend power and torque on my Serval so I ran PT's and choked it to death and made the power band so short and strong that that I had to run a 16T front sprocket in order to outrun 50cc mini quad! Lol I was wrong there so I could be wrong here too. I was basing my recommendation off what I've been told about the 10 mil CP Power Plants that utilize the stock four bolt intakes and Reed cages. Have you ever heard about any problems with the 10 mils and standard four bolt intakes?

Here's a carburetor with a non-tapered riffle bore to give you a idea of what I'm talking about. This was done on 80cc two stroke dirt bike carburetor that was used for 300ft dirt drags so taper boring wasn't done because they wanted the maximum bore and the benifits that gained from taper boring wouldn't be useful for a straight line drag racing application. The rifffle bore spins the air entering the carburetor bell in a vortex motion resulting in increased velocity and and decreased turbulence as it passes through the carburetor venturi therefore creating increased vacuum draw on the jetting circuits which intern increase fuel atomization. This increase in velocity also increases the pre-atomized fuel/air ability to pass through the intake and ports at a higher rate of speed resulting in increased performance and throttle response. Well that's my take on it anyway.

What did you end up doing Craig? I built a 10 mil 535cc PV Cheetah for tail and recreational use and I ended up buying a set of new 38mm Keihin PWK Air Strikers to run on it. I chose the Air Strikers because the Honda 250R guys love them so I figured the PV Cheetah would perform good with them because it uses 250R intakes and V3 Reed Cages. I've always heard the PWK Air Strikers couldn't be bored like a standard PWK or PJ Keihin Carburetor. I don't know if there's any truth to that or not. I've also heard that the 10 mil Cubs and Servals push the 4-Bolt Banshee Intakes and Reed Cages to their CFM limits. If that is indeed the case a 38mm+ carburetor could create turbulence and actually hurt performance or at least prevent performance gains. When I was shopping engine builders and deciding between a 10 mil 535cc PV Cheetah or 10 mil 521cc Serval I had more than one of them tell me to go with 35mm Keihin's if I built a 521cc Serval Trail Motor and one of them was Jeff at FAST. If I was in your shoes I would keep your 35mm Keihins and send them out to Brandon at Wild Cards and have him taper bore them to 36mm....... OR even better send them out and have a 36mm tapered rifle bore done. That would be bad ass! The super mini racers swear by the riffled taper bore, they gain power across the entire power curve with it. They claim the carburetor bore can be increased by 20% over a standard taper bore without the loss in throttle response and low end power/torque that's seen when carburetor size is increased. I think riffled 36mm PWK's would be perfect for a 465cc Serval running a set of Hi-Rev Pipes. This is just my opinion I'm not saying the other advice and recommendations that the other members have given you is wrong or bad in anyway. I'm just telling you what I'd do or look into if I were you.