Here is there website and phone numbers. They have retail pricing on their website, if you are buying that much fuel you should be able to get a hell of a deal. If Klotz won't give you one, find a local dealer and they should be able to.

Toll Free >> 800-242-0489
Tech Line >> 219-490-0489
KLOTZ Performance Lubricants

 

Hello - I guess I need to re-introduce myself to most of you folks. I'm Pam, I've worked for Powroll for about 7 years. I used to spend a bunch of time here, but haven't in the last few years.

First off, I want to apologize to Raptor 720 for not replying to his message on ATV Nation.

I guess he didn’t see my post stuck to the top of the board with info that I’d be on vacation from April 26th through May 6th. Unfortunately, he posted his questions on the 30th!

If you’re not familiar with Powroll, we’ve been building four stroke performance stuff since 1964. Nope, that’s not a typo – ’64! Yup, the company’s older than dirt!

For reference, the best way to reach Powroll regarding our product is to go directly to the source. We’re available regular business hours, 8am – 5:30 pm Weekdays. Our phone number is 541-923-1290. Or you can email us at mail@powroll.com. I can’t guarantee that you’ll speak to me, but anyone you talk to in our office can typically answer basic technical questions.

Raptor 770 states: “The 771cc engine is made by using a 105mm piston, a 89mm stroke (+5mm stroke). Assuming that we are talking a stock 5.374 rod length, at 8500 rpm, your piston will travel 8211.9 feet per minute.”

Raptor770, You might want to get a refund on that calculator! Here’s the numbers I came up with. Piston speed with our 89mm stroker is 4,963.9 fpm. For reference, stock piston speed is 4,685 fpm. We haven’t had any rod failure problems yet, and the test engine’s been running with the 770 for about 5 months now.

If any of you want to figure piston speed yourselves, here’s the formula: RPM x Stroke length (in mm) divided by 152.4. This will give you piston speed at the specified rpm. Powroll recommends no more than 5,000 fpm on any engine.

Velocityraptor called and talked to one of our technicians about the Raptor. He actually spoke to Pete Fisher, the owner and head R&D guru here. Anyway – some of the information was taken out of context. Below is the real scoop.

<<Could'nt rev motor over 6000rpm's without completely melting it down
thay had troubles with burning holes through the back of the heads "via nos">>

What Pete said was that the engine is best setup as a torque motor. He cautioned you about over-revving big bore and stroked engines.

He also told you that the only engine failure we’ve experienced was when the owner of the quad melted the backside off the PISTON (not heads) when he ran a complete bottle of Nitrous through the thing without proper jetting (that puppy was lean!).

The “back of the heads” information Pete gave you didn’t have anything to do with pistons. He told you that the Powroll R&D department cut off the back of the head and re-welded it for a better port angle.

He said when he spoke to you, the conversation seemed odd, like you may have been a bit distracted. I’m sorry if he wasn’t clear enough when he answered your questions.

There’s also about a bazillion other weird statements in this long thread that I’d love to discuss, but I don’t even know where to start. Especially since this reply is already too long!

Only two more things then – Giving out cam grind numbers doesn’t hurt anyone. Our customers get complete information with every Powroll cam they buy – and our lift numbers are posted for most of our grinds right on our website. We’ve always believed that we’re better off giving our customers all the information they need to make an informed decision – even though it means we’ve had more than our fair share of stuff pirated over the last 35+ years.

Last but not least – Where and when are the next Four Stroke Wars? We haven’t been formally invited, but maybe we’ll still show up…

 

I would like to clear up the numbers between Pam and Raptor720. Pam you or Pete have calculated the Mean(Avg.) Piston Speed and Raptor720 has calculated the Maximum Piston Speed. Neither are wrong, it really just depends how you want to determine your livable range. I know most performance shops compare Mean Piston Speed rather than Max.

Just FYI I did find some info on Indy cars and their related piston speeds. They rated their piston speeds as Maximum, but really calculated Mean Piston Speed(Lets hope it was a typo!). They were also approaching 5000fpm, but were doing everything they could to reduce the piston speed and improve engine reliability.

 

Pam,

Glad to see you here in this Monster of a post. We have 2500 views, but very little of it on the 770 topic.

First off, I sent you a post on your favorite web site on 4-21-02 and followed that up with an e-mail to your powroll addy. With no response, I posted another message in another forum on 4-30-02. In all three cases, there was no response (granted you appear to have been on vacation from 4-26 to 5-6).

On the piston speed calculations, my fairly expensive engine math programs are correct. No need to toss anything in the trash. You happen to be calculating Average Piston Speed where I am calculating Maximum Piston Speed. Your numbers are correct for Average Speeds while mine are correct for Maximum Pistons Speeds.

Sure, we can build from the APS numbers; however, I want to know my MAXIMUM Piston Speed "MPS" so that I can properly figure a safe load (positive and negative) for the selected brand/length connecting rod, piston, etc. We all have heard the story that a chain is only as strong as its weakest link NOT the "Average" link. Average implies that there are numbers above and below your target. Considering the high cost of replacement Raptor engine parts, I will continue to engineer and build from my MPS numbers. Your motor may be fine at your design rpm -- I know that the motorcycle engine builders have stretched the old engineering limits in the past few years. I am still old school and will work to the lower range for safety.

Your 770 project may not yet have experienced a rod failure -- perhaps that rod/piston combo was above the average in strength. I have seen the stock rods fail in the Raptor as well as the SZR/TZR and MZ 660 models. Carillo makes a great replacement rod which may take the weak link out of the rod area and move it to the piston (another area of high failure percentage).

By the way, here is another formula that can be used as a quick RPM ceiling tool. 30,000/stroke=max rpm. Using this formula, your 770 engine should never see more than 7700 rpm (just under where the cam and head really start to work) while the stock stroke can see 9070 rpm (well above max power -- provides some safe over rev).

Jon
aka Raptor 720

 

Glad to see you on here Pam. Its always nice to have another educated person on the forum for information. That was one trick looking Raptor.

 

Sorry about the crossed communication there Jon. We've always calculated piston speed with the formula shown - I'll let Pete tell you why (he's the tech guru!).

Sorry to burst all you folks bubbles, but we don't typically give out dyno numbers. The reasons are many, but the biggest reason is because we don't use the same type of dyno that everyone else does.

We feel that a hydraulic dyno gives us a more accurate reading for the four stroke engines that we work on (we feel the drum style dyno works better for RPM-style engines such as two strokes and roadrace bikes). Our hydro dyno actually measures torque, and we can mess with the load and really see if an engine is producing power where we need it for specific applications.

The numbers we get from this dyno are REALLY low compared to typical dynojet numbers. If you'd like to read more about the differences between dynos, check it out on our website here: http://www.powroll.com/tech_specs_dyno.htm

If you folks really want to see numbers, what we like to do is compare percentage of increase. You know, dyno a bike in stock form, then again when you're done tweaking. Add everything together and get a % of increase. This takes away the 'different dyno' arguement. Of course, companies can still fudge these numbers [img]i/expressions/face-icon-small-smile.gif[/img]

Dynos are great diagnostic tools - but they still don't show you who's fastest or what engine works best for YOU.

In fact, the Raptor 770 that we built wasn't even designed as a drag bike. The owner wanted lots of power so he could drag race a bit, hillclimb and still trail ride at the Oregon Dunes. We built exactly what he asked for.

Is this Powroll Nitros 770 the fastest Raptor out there? Heck no.

No matter how big or fast you build something, there's always someone faster. Always.

My advice? Be honest about what you REALLY want out of a performance engine (how often do you want to rebuild, what do you want to beat, is it stricktly drag race or do you want to play ride, etc????), then find the company that will give you what you're looking for.

If you are specific about what you want, "I want to be able to beat ported and piped Banshees, I want the engine to last a year without a rebuild and I also like to trailride with my wife occasionally", and you call a bunch of different shops and find one that you're comfortable with, then you'll probably be happy with the outcome.

On the other hand, if you call a bunch of shops and ask for a dyno number, then send your engine to the company with the biggest numbers, you could definitely end up disappointed.

 

Hey pam ive been trying to get you guys on the phone for two days no luck.ive been trying to see if you do any thing for the ds yet or do you only work with slow bikes[LOL]please email me @ yocabet@aol.com .later

 

I hope that Jeffinrivercity shows up, but I can tell you now, that he will not be the only DS there. I full well plan to be there myself, and am aready trying to determine what I'll have for the war. I would love to see Ron Woods racing present a bike as well as Trinity[if they are up and running with their DS program]. I've talked with Harry[from Trinty], and know that his current plans don't call for anything as extensive as my offerings, but it would be great to see what they can do as well. I genuinly have a good deal of respect for what Harry and Ron have built, and look forward to putting my work up against theirs.

Doesn't that put the preasure on the Raptor crowd. If you guys have the majority of the bikes, but a DS wins, I don't think that would look good for the Raptor owners. I love being the under dog, no one expects my motors to win.

 

Knutz- I believe that your motors are the best shot the Ds has. But this race is going to be about $$$$ . Who got the most hp for money spent.

Are there going to be any rules about a 10 minute romp thru the sand? or a trail ride? Don't want a straight drag machine to take the crown.

Knutz- where are your motors in texas. Very interested in hooking up for a ride with them.

 

<< Knutz- where are your motors in texas. Very interested in hooking up for a ride with them. >>



The wicked 760 that I'll be sending out this week is going to Blossom, Texas. I can't remember the towns that the 703's went to, and just haven't gotten a chance to look them up. Unfortunatly, I don't keep my files according to city or state, so it would take some time[that I don't have alot of] to find those files. Sorry.