HPD has the clutching expertise anyone could want. They are a smaller operated business, and dont have the vast time on hand to "phone chat", that's why mike is only available from 3-5 central time for tech help. Mike is the man on clutching. If you realized on their website, the clutch spring chart is not their own, rather an oem Polaris chart. If you want to start grinding on your own weights, you had better buy Aaen's handbook, a gram scale, their grinding block, and be prepared for some thorough testing. If you dont have a good accurate tach, it will be pointless. There comes a time when you realize it's not worth it to try and do it yourself. Trust me, Ive already been there.[img]i/expressions/face-icon-small-happy.gif[/img]

 

If you REALLY want to know all there is to know about clutching the Polaris belt-drive, order Aaen's book called 'Clutch Tuning Handbook'. It goes into great details about everything from engagements, upshifts, downshifts, friction loss, etc. It even has a section on weight modifications (altering the curve of the weights and how it will effect performance).
Yes, you do want to be careful about too much tension on the belt. Keep in mind, that power doesn't appear from anywhere. If the belt is being squeezed twice as heavy as it needs to, not only do you risk overloading the belt, that force has to come from somewhere, and can be a parasitic power loss. If you really want to cut parasitic loss, switch the secondary over to a roller-style. Less friction, faster reaction, more durable than stock (In fact, the new Sportsmans 500 & up now come with roller secondary clutches). Only drawback is higher cost. To REALLY get the clutch just right, also invest in a 'tiny tach' or equivilent. Knowing your exact RPM at any given time will help greatly. Sometimes the RPMs go up or down as the clutch upshifts under acceleration. Knowing about what speed this happens can help greatly for getting the tuning just right. In MOST cases, if you are getting a new helix, the double-angle ones will help tweak out that last little bit of effeciency out of your machine. Wherever you get the helix/roller kit should know which one should best suit your needs. Probably the biggest advantage of the roller kit for trail riders is the almost instant response you can get from them. It is hard to explain, but it gets rid of most of that 'lag' you feel when you hit the throttle before it starts accelerating.

 

Thanks again guys.

I've talked a bit w/Olaf Aaen and he's discouraged me from getting into trying to hunt for custom curves. I'll at least reconsider my feelings about HPD and clutching, but I do prefer RCR and Aaens up front support and information sharing, and I prefer to reward support with sales dollars. I guess some folks take that information and shop it so I kinda understand HPD's points. The refusal to alter or discuss kit specs just made me irritable. I'll try not to over-react. I can say that when I was pipe shopping I was impressed with HPD then. Athough then I spoke to Darryl and now for clutching I got somebody else.

Anyway, good advise from all so I'd better listen to it. I'll look into the roller secondary was well. I suspect its more money then I outa spend, but we'll see. Any suggestions on who's hot there?

Present thinking is dual helix, and two new springs. Maybe $100 bucks. Olaf wants me to use much heavier springs then I'm inclined to use (as does HPD). So I may do both and try it each way. TBD.

Lastly, I've put up without a tach and/or EGT long enough. Anybody want to recommend an electronic tach/EGT combo that support both the banshee and the scrambler?

Thanks a lot guys. Its been real helpful. Once I get something done I'll let you know.

Dan

 

Oh for Gods SAKE!!!

I just figured it all out. Aside, that is, from reading different spec's for the same product. Before I go on I'll explain this last. Here are the various published specs for the SAME POLARIS PART NUMBER. Its 7041132, or the infamous Polaris "White" primary

eng load full shift load rate
Aaen as excerpted from their book: 35 111 76
HPD specs 47 136
graphs on HPD's site 35 142

As you can imaging, that alone is a pain in the ***. But, as I've likely mentioned, I wanted to lower the engage point and push my shift rpm up. EVERYBODY thinks I'm nuts. Of course, everybody, myself included, assumes I was starting from a stock clutch. Guess what? It ain't. I think I'm gonna hunt down the dealer, kill him, sacrifice his... uh. Wait. in todays world maybe that could be taken seriously.

You see, I've mentioned to hpd and Aaen that I thought my primary shifted high, and just what was the stock spring please?. Everybody keeps insisting its a green/blue spring. Yeah, OK, says I, if you say that's green/blue, but it sure looks plain metal colored to me....

Well guys, I don't KNOW, but I just found the specs for a polaris "plain" clutch spring. It engages late and shifts out early. The VERY thing I'm bitching about. And its recommended by HPD (darn, now that I've used their web site to figure this out I owe them too!) for higher engagement on a stock motor. Had I mentioned I'd bought this used? That it came w/ITP rims and a K&N and was otherwise stock? I'll bet the color on a green/blue primary spring is pretty darn obvious and that my plain spring is a plain spring. sigh.... Oh well, at least it'll be easy to fix now.

Ya know, 4 days ago I didn't know a darn thing about PVT. 2 Days ago I was dreaming about them. Soon I'l be having nightmares.

Suddenly life is good, all the recomendations people have made fall in line, and I'm happy. Hell, now the white looks rather conservative. I'm thinking maybe yellow.... Even better, now these kits I'm disdained may actually make sense. Sheesh!

Springs - $15, Helix - $45, The value of doing your own research - Priceless.

 

If you plan on keeping the trail pipe, the white oem or yellow spring is really useless for you. You need a spring like the plain HPD6 one. It will engage early and shift late just like you want. You will need to run it with 53 gram weights. If you buy a yellow or white, it's gonna be a waste of money. Trust me, I've already been there and done that with 2 different bikes. Bubba

 

I just re-read your last post. The plain OEM spring is far fron HPD's plain spring. I believe you are thinking they are the same.

 

When I worked on my Xplorer clutch, the stock spring was green & blue.

The bare metal one from Polaris, in my book would let the engine rev far too high for normal riding (I guess you figured that out).

If you talked to Olaf Aaen, pay attention to what he said. He can probably get more out of a clutch than any one man I know of, with Rick Ritter right there with him.

 

Bubba: No, I assume its a polaris plain. Can't tell of course. HPD's chart lists both. Gee I'll be happy when my polaris service manual gets here. I do have a parts manual online. Maybe that'll help.

Odd you should mention the HPD6. Whoever at HPD I spoke with that made me feel they weren't up to snuff kept insisting I didn't want that spring. It seemed interesting to be as well. Hell, they're only $15! I'll buy several.

Farmr123: Yeah, I trust Rick and have suggested him several times. Funnily enough I don't really want to use Olaf's advise. He wants me to use springs so heavy I think it will just rob HP. I may just call rick again. I spoke with him last week as I was beginning this odessy from hell, but hated wasting his time. I knew absolutely nothing. I've studied this thing a bit and it may be time.

Sigh; so many people you want to spend money with.... Its just another problem. Aaens's faxed me docs and I've used those docs and their web site. I've not felt anybody wanted to tear into it other then Rick, and while distrustfull of at least some advise from HPD, I've used their website heavily. So fella's, How do I resolve that little moral challenge?

As always, thanks LOTS

dan

 

Yep, the parts manual shows its a white spring standard. Now if there was only a way to know which one this plain looking one was. sigh... Darn I was close. Course, if its white then ordering a white or a green isn't solving much is it? Hpd6 or yellow.

Course, I may yet grind on the weights in an attempt to lighten the tips up a bit. I wonder if I can add weight to middle area somehow, sorta like the Thunder Cat snowmobile weights..

 

Just remember, the total weight of the weights will affect the rpms. When you take weight off of the tip, you will cause the clutch to lag on the shift until later as it starts moving the belt up. That's why the trail profile is heavy on the end. The one thing to remember is that you want the rpms to be at 6700-6800 when at full thottle while maintaining a straight shift curve. That's where the pipe makes it power. Bubba