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Discussion Starter #1
Hi all- I'm new to the forum.. and i have just a few questions
I have a 1981 AC El Tigre' 5000 with the 500cc free air motor, and i want more power. I was wondering if anyone has a set of pipes for this machine. I see Aaen makes a set for roughly $500.. i was hoping to find some used, or alot cheaper. Also, when i got this sled the primary clutch was replaced with a comet duster. I have two 102 clutches, but am having alot of trouble tuning them.. does anyone have a good reccomendation for springs and weights? I have rebuilt the top end and have many spare parts and i'm willing to tune and experiment. i would also like to grass drag in vintage drags, is there anything else i could do?Any help is greatly appreciated! Thanks again!
 

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I had an '81 5000 Tiger I grass dragged in the old days. It took me a while to get it dialed in, but I kicked some pretty serious butt once I got it! First, don't waste your money on the Aaen pipes. Unless they've changed them since the early '80s, I'm guessing they haven't, they'll just slow your sled down. I bought the pipes, 38mm carb kit, and 102 Comet clutch "specifically calibrated" for a 5000 Tiger from Aaen. It would run 90 mph (on the speedo) bone stock, and 85mph with the Aaen junk on it. Maybe I'll get bashed for being so blunt, but at the time, I was pretty PO'ed to spend that much money and have my sled run worse. To be fair, I have run some Aaen stuff on other sleds that worked good, but their 5000 Tiger stuff wasn't it.

I'd get rid of the Duster clutch if I were you. They aren't built heavy enough to handle the 5000's horsepower, and there isn't much you can do to tune them. If I were you, I'd probably check with HPE and see what setup they recommend for a 102, seeing as how you've already got one. I remember talking to Larry Coltom on the phone there back when I was racing, and the guy really knows his stuff about clutching. His clutch setup for your sled would probably be best.

And most people will tell you I'm seriously whacked in the head for saying this, but if I was going to go grass dragging, I'd locate an original hex clutch and set that up just for racing. I experimented with a Comet 102 off and on for years on my 5000, and I could never get it to pull as hard in 500' on grass as the Arctic Hex did. I remember I ran the stock ramp, but ground it slightly just to raise the engagement I little, and went to a heavier weight. If you really want to know, I'll dig out some of my old manuals and see if I can come up with the exact setup I was running. But I'm telling you, it WORKED! I can also tell you the old Hex is a high maintenance item. I used to pull mine off before every race and clean it thoroughly. If there is one speck of belt dust inside anywhere, it won't shift consistantly. And the hex shaft has to be polished until it shines like chrome. I used to clean the clutch the day before a race, put it back on the sled, and not start the sled again until I actually got to the races and ready to make a trial run.

Sorry to get so long winded. You've given me some awful flashbacks! I had a lot of fun racing that sled. Every now and then I still dig out some pictures and reminisce.

There is a lot more stuff I did, but I don't want to clog up the whole board! Maybe you can e-mail me. I'd be glad to help you out any way I can.

Thanks for the memories!
 

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Discussion Starter #3
Wow! now that is what i am looking for! I was hoping some one like you would reply! I don't exactly care for the comet clutch either, but i don't have a hex. You still don't happen to have one kicking around do you?? I would also be interested in knowing what else you did! scret I would really like to clean house this year! One thing i was thinking about doing is flipping the track around, and maybe studding it. What did you change for gearing, secondary, etc? any info is greatly appreciated. The sled i got was in excellent shape, i bought it from an older guy who is the origional owner. he said he took the "racing" clutch off so his grandkids could ride it safer, and traded straight up for a duster. Arg.. some people! What should i do for exhaust? leave she stock pipe?? I'm really not all that impressed with it becuase it restricts flow so bad it extends the springs holding it to the header, and the header seems somewhat restrictive also. I'm working on it as we speak.. oh yea, what is your opinion as for carbs too? Thanks for the reply! Rockerdude Feel free to e-mail me at [email protected] with your suggestions.. Thanks!
 

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You shouldn't have any trouble coming up with a hex clutch, most people hated them. Ask your local Cat dealer if he's got any old ones laying in the corner. They almost all do. Just make sure it's for a 1 3/8" belt. Most were for 1 1/4" belts. The '81 5000 El Tigres were the only Arctic Enterprises sleds that came with a 1 3/8 hex clutch. But some of the Artco sleds came with a 1 3/8" clutch with an extended bushing on the movable sheave. This would be a stronger clutch if you can find one. Usually all you need to do is replace the hex bushings and spider assembly and they're as good as new. Dennis Kirk carries all of the parts. Use the stock '81 5000 ramps, they worked the best of anything I tried. I'll have to study my books and see if I can remember what weight I used. I remember it was heavier than what came in them stock. That 500 FA is a really torquey motor, so you won't need much engagement rpm. I ground the ramps to engage at 4000 rpm, but stock (I think it was 3600) will probably work.

Yeah, turn your track around, but don't stud it. Studs will kill your top end. To make it hook up, drop the mounting points of the front swingarm of the track suspension. If you look inside the tunnel, you'll notice another hole about 1" lower in the plate riveted to the tunnel to beef up the mount (Sorry, I can't think of a better way to describe it!). Drill that hole on through to the outside and bolt the front swingarm into that hole. You'll find it makes a HUGE difference in weight transfer off the line! Hang on tight the first time you try it, it'll wheelie like crazy! By doing this, you won't need any studs. And you need to build yourself a good slide rail lubricator, too. And build an axle and add a set of idler wheels right where the front spring sliders are. There is a lot of drag right here with the stock setup.

As for gearing, I went three teeth smaller on the top sprocket. You'll have to eliminate that goofy spring thing that tightens the chain when you do. What I did was take a small piece of strap iron, drill some holes in it to fit over the rubbing block pins to hold the chain tension properly, and cotter pin that in place. Otherwise, the chain will slip and you'll ruin the sprockets (Ask me how I know that?).

As for the secondary, I modified my own helix by taking one that was originally 48 degrees 44 minutes, and ground a 45 degree angle on about the first 1/3 of it for a stronger hole shot. This was back in the days before the off-the-shelf, CNC machined helixes you can buy now. See, I was a pioneer! I would probably look for a 47 or 48 degree helix now. There wasn't much of a selection back then.

As for your exhaust, are you sure it isn't plugged? Something doesn't sound right about yours. They normally worked just fine. You might have a mouse nest in it. Take it off and try blowing through it. There shouldn't be any restriction at all. Also, when you're racing, DON'T COOL THE PIPE! A lot of people do this and it's wrong. Any tuned exhaust is designed to work hot, not cold. The temp. of the pipe effects the flow.

The carbs are fine. If it has an air box, take it off. As I recall, they came with 230 mains. I think I ran 210s in mine. It seems like I had the needles dropped to the leanest setting, too. When these sleds are jetted right, they pull just unGodly off the line. I always ran VP C-12 racing fuel. It made good power and made the engine run cooler.

You got me on a roll now man! Let me know if you have any more questions. If I think of anything else, I'll post again.
 

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Discussion Starter #5
yet another helpful response! Thanks for all of the info.. I'll try some of the things you suggested, and i'll post back. if you have anything else please feel free to add! I really love this sled, and some friends of mine can't believe how spunky it is! slomo Definatly a sled to hold on to! :D
 

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Man, you don't know how many times I've wished I still had mine! They're a really torquey, low end engine, so it takes a little different setup approach to take full advantage of it. I had my own 500' test strip. One year I set my odometer to 0 when I started testing for the season. I had 80 miles on the odometer before I went to the first race of the season. I put all 80 miles on it 500' at a time. I had the drive clutch apart so many times I wore the threads right out and had to throw that clutch away and buy a new one! Yamaha won all the grass drags back then, but I was bound and determined to beat them. It took me a while to hit the right setup, but once I did I spanked them regularly! I even PO'ed a few Cat guys. In all the time I raced that sled, I was never beat by a 6000 Tiger, either. Some of 'em didn't take it real well!

Can you tell you've got me pumped up about your 5000?! I just wish I was there to help ya! Good luck with it and keep me posted with your results.
 

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Discussion Starter #7
Thanks for all your help! i know i'll definatly use it. I've been working on the sled lately, and i don't know if it's too hot, or what the deal is, but every once in a while it is just doggy. like running on one cylinder almost. I by-passed the kill switch, and tried plugs, tuning on the carbs, and i'm stumped. maybe the exhaust is the problem. i know it's not plugged, but it leaks quite a bit when i rap on it. Thats another reason i want some twin pipes. Also, what rpm should i clutch it to? I'll try to get ahold of a hex clutch, but if i can't i'll have to tune the comet. I know what your talking about with the suspension and track, and i will do that. Is there any way i can get more compression out of it? I have several spare heads and i work at a machine shop. How much should i take off? I will geep working on it to try and get it straightened out, but now that i think last season i couldn't get more than 75 or 80 out of it, on a hardpacked gravel road... so i think clutching has somehting to do with it. I have also noticed the clutch seems to have a wobble like it isn't running perfectly true.. and i need to check the alighment or offset. Do you know what that should be? This sled is in nice shape, now it's time to get it tuned right. Thanks for your help! i wish i was aroung back when you could get performance parts easily, around here the arctic shops all threw out their old parts.. bang your head
 

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"I've been working on the sled lately, and i don't know if it's too hot, or what the deal is, but every once in a while it is just doggy. like running on one cylinder almost. I by-passed the kill switch, and tried plugs, tuning on the carbs, and i'm stumped."

As I recall, there is a situation where the kill switch under the throttle lever can go bad, and bypassing the switch doesn't do any good, because the switch is still in the circuit. If you've got a wiring diagram, study it close and I think you'll find what I'm talking about. What happens is the engine won't quit, but it loses just enough contact through the switch to cause a misfire.

"maybe the exhaust is the problem. i know it's not plugged, but it leaks quite a bit when i rap on it. Thats another reason i want some twin pipes."

Where is it leaking? Are the springs stretched out on the flex joint? It's your money if you want pipes, But there is a lot more potential in what you've got there. If you are really bent on buying pipes, try to locate a set of HPE pipes for your sled. I remember hearing at the time that they worked pretty good.

"Also, what rpm should i clutch it to?" It was 7200 on the tach on my sled.

"Is there any way i can get more compression out of it? I have several spare heads and i work at a machine shop. How much should i take off?"

The critical thing here is ending up with the proper squish band clearance. Right now I can't think of what that number is. .060" sticks in my head, but I won't swear to it. Generally, you can get away with .015" to .020" and be OK. Although I'd run at least super unleaded gas if I milled anything off.

"I will geep working on it to try and get it straightened out, but now that i think last season i couldn't get more than 75 or 80 out of it, on a hardpacked gravel road..."

Try this again on snow and see if it goes any faster! :lol:
That Duster is killing you here. Ash-can that thing!

"I have also noticed the clutch seems to have a wobble like it isn't running perfectly true.. and i need to check the alighment or offset."

I repeat...ash-can the Duster! The offset measurement is probably different with a Comet than with a Hex. I remember the center-to-center is 10.2" I'd recommend calling HPE (High Performance Engineering) about the clutch alignment. I think Larry Coltom is still there. I'd ask for him when I called. I'm telling ya, the guy's good, and he'd be right at home on your old Tiger.

PS: Larry might be able to help you finding a hex clutch.

Stay tuned for more information!
 

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Discussion Starter #9
I know about the kill switch on the throttly, and it isn't in the circuit, besause i simply tied the two together with a small jumper wire.. so to speak. I'm confident that isn't the problem. I switched the coil and wire assembly today and that seemed to help, maybe one of the wires was arching to the head??

The exhaust is leaking at the flex joint, and the springs are tight, but the force of the motor makes it expand. i've tried new springs, and i'm positive there isn't any restrictions in the exhaust, but it leaks so bad when riding you can see it come out the front scoops. I also don't care for the way the header is resigned, being how it downsizes so much from the size of the port in the cylinder. The only way i'm afraid it will stop leaking is to weld it solid, but if i do i think it may crack, then i have a bigger problem.

By the way there was snow and ice on the road!!! Geez... j/k! That was after i put in the 102.. but the setup from comet suckes so bad thats all it had! I tried fooling around tuning th clutch, but it's giving me alot of curve balls.. normally i can clutch my other sleds fairly easy, but this one... I feel like it's partially the comet. and the wobble is like a bent crank, but i'm positive it isn't. it's like the taper isn't quite straight, but i think i got that straightened out now.

I'll call HPE tomorrow if i find the number, and talk with larry if he's still around. Hopefully he can help with my offset and tuning. Oh.. i also came across some VM-38 mikuni's for a good price.. should i buy them? or would i be better off leaving them alone?
 

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I raced in the stock class, so I learned to make the most of what was stock, exhaust, carbs, etc. IMHO, I think the porting is such that bigger carbs won't do you much good. I never tried the 38s I had with the stock exhaust, so I can't tell you how that works. One thing I did do was build up the inside of the Y-pipe with braze and then grind it to match the exhaust ports. I'd take the heads off and feel down through the ports to make sure they matched. It sounds like your flex joint is worn out. Could you just cut it off and weld a new one on? Dennis Kirk used to carry new ones, but I don't know if they still do.

One thing I always wanted to try was cutting the piston skirts. If you have access to a lathe, this one's pretty easy, but you have to ruin a set of pistons to find out how much you can take off. I'd start by chucking up a piston and turn about .020" off the skirt. Then put your engine back together and see how it runs. If it runs OK, pull the pistons again and take another .010" and try that. When you've reached the point of no return, the engine will fall flat on it's face power-wise. Here is where you take a new set of pistons and cut them to the dimension that made it run the best. I'd check the skirt length along the way by measuring from the piston skirt to the wrist pin with a depth mic. I did this to a Jag 340 fan, and along with the other mods, it would hang right with my 5000 El-Tigre to about half-track at the grass drags! Cutting the skirts gives you more duration that the intake port is open on a piston port engine. I got an idea that if you put those 38mm carbs on after you do this you'd see a big jump in performance.

One thing on clutching, you'll get kind of an overdrive effect from the Hex clutch. Even though the sheaves are the same diameter, the belt comes closer to the top of the sheaves on full upshift on the hex than the 102. So you'll get more top end with the hex. This particular engine is really torquey, it doesn't like to be overrevved. That's what threw me for a long time. Performance will drop off fast overrevving it. So stay heavy on weights and run a real soft preload on the driven. I used to just put the driven clutch together without winding in the 1/3 turn preload on the spring. I had mine set up so soft that it wouldn't pick the belt up out of the driven on it's own. At the starting line I'd hold the track off the ground and let the track coast to a stop without touching the brake. Just before it stopped, it would finally work the belt to the top of the driven. (I guess that's more than one thing!) It worked good to play a psych game on the competition. When I ran it through the pits it sounded like it would barely move itself because the clutches never backshifted. But you should have seen their eyes bug out when it came off the line with the skiis pointed high in the air! slaphappy

God you're giving me some awful flashbacks!
 

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Discussion Starter #11
Well i found a hex clutch, one that came off an 81 el tigre 5000, so it should be right.. I'll pick that up on thursday. Could you do me a favor and look back and see what weights you used? When i get this one i'll rebuild it, and get the better weights. What all should i check or replace, since this is my first hex. I already have 48-44 or something helix, and i'll be getting a new gear for the top chaincase gear- dropping three teeth as you suggested. What will it top out at with the different gearing? Also i know what you meant about the suspension mounts, i'll be doing that next. so your sled really ran that quick without winding the secondary 1/3 turn? I would love to try your exact old setup, because in a few weeks i have to race a buddy on an older crapped out indy 600 at the drags.. and would like to whomp him in front of everyone!! I have it running alot better, and i too have leaned out my jetting, same is you incidently because thats what i had last winter when i looked into that.. What else could i try? I called HPE and there isn't a larry coltom anymore.. and they were absolutly no help. They weren't willing even though i said i ordered through them, and what not, all they suggested is some heavy hitters or something that i could tune myself, and thats it. Their tech didn't even seem to know what i was looking for, they said i could check their catalogue. I'm also going to try modding the piston skirts.. sort of like camming a four stroke. I'll do this on my spare motor, and might only take off .020''.. mill the heads .015", and try the 38mm carbs all at once. Not exactly the same time, but new pistons are spendy when paying for a new car! Oh yea.. what kind of speed were you running in 500'? just curious what i can hopefully get close to
naughty
Also- do you know that stock number of teeth on the gears? i would like to get the gear before i tear into it. Thanks!
 

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As far as the hex goes, you'll probably have to replace the spider and rollers. The biggest thing it to make sure everything fits tight in the swing arm pins. Sometimes the ramps get worn crooked from running the sled with a worn out spider, so you'll have to replace those. One thing you'll want to check is make sure there aren't any burrs or worn metal in the way of letting the ramps set down into the groove where they belong, or the clutch won't shift consistently (Ask me how I know that, too?!). Replacing the hex bushings can be kind of tricky, but I think you'll get it all right. Just do a test fit before you Loctite the bushings to make sure the bolt holes line up. And make the line-up marks cast into the movable sheave halves line up. FWIW, you can't mix and match the two movable sheave parts and the fixed sheave parts from other clutches without having it re-balanced (Ditto on the "Ask me how I know that?!"). Basically, all you're going to re-use are the three major pieces of the clutch.

You've already got the right helix, but without grinding a 45 degree angle on the beginning 1/3 of the ramp, you'll have to run some more spring preload than I did to keep it from bogging off the line. It should still work better than the stock 45 degree helix, though.

My experience with dropping the gearing three teeth made no difference on top end. There used to be an old air strip we ran on and it would top out at about 90 mph with either the 24 or the 21 tooth sprocket.

That's too bad that Larry is gone from HPE, I wondered if he's still there. You'll probably find you're on your own setting up that hex clutch (Other than me, of course! thumbguy ). Like I said before, most people hated them, but I still maintain that they're the best clutch ever made for drag racing. The drawback is they don't backshift. But if you have to back off the throttle in a drag race you're going to lose anyhow, so what's the difference?!

I can't remember my times for 500', but I do remember the speedo would be just shy of 80 mph at the finish line. FWIW, I weighed about 130# then. I'm just slightly heavier than that now ;)!

I'll try to get time to look through my old manuals tonight and figure out what weight I was running and let you know. It sticks in my head that the stock weight part number ended with -279 and I ran a -278, but I'll double check.

Unless your buddy's got his 600 dialed in pretty good, I don't think you'll have much trouble beating him. They're a heavy sled to get under motion in 500'.

I'll get back with you ASAP with the weight info.
 

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Discussion Starter #13
hopefully I'll be able to get the clutch, but the guy on the phone told me they have a few now, they didn't six months ago, or maybe he just kept trying to get me to buy a new comet. Any how, he said he'll find the tightest one and set it aside for me. What i'll probably end up doing is tear it apart, clean it, but it back together and order a bunch of rebuild parts. I'm eager to try it out on my test track (i live on an acridge) and compare to the comet and get a baseline. I've found that with the comet i'm slow off the line, but once my RPM's get up, it wheelies and pulls hard. I also have to keep the driven spring in the tighest hole, or need less weight in the primary. Should i use any kind of filter over the carbs? on my other sleds it's just raw air, but i was thinking about some wire mesh style filters. I'm also going to order a new flex joint, and take some pistons and heads in to work. I'm going to flat out try .025 and leave that on the pistons, and .015 on the heads. if that helps i'll just leave it, if not oh well. all of that, plus gearing, and suspension mods, and the hex, i think should make for one snappy el tigre' The same place that has the clutch said he has a 6000 with pipes, and said the 5000 was very similar in pipe sesign, so i may try them and bigger carbs. We'll see. I'll definatly let you know how my grudge match goes.. a kid on a f-5 won't race me, because he saw what my old TX440 will do... ;) talk about spunky!! not fast, but quick. too bad it's not green HAHA :D
 

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I've found that Comet clutches in general tend to be soft off the line. That's where the hexes are extra strong, coming off the line.

I didn't use any kind of filters at all on mine.

One other thing I thought of, you may have to file the inside of the hex bushings to free them up on the hex shaft. There needs to be enough clearance so there is no drag at all sliding the movable sheave up and down the hex, yet it doesn't want to fit sloppy, either.

I'll have to get back to you on the weights, I got home to late to look.
 

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I just looked up the stock clutch weights via the net and the part number does end in -279, so I'm about 99.9% sure the weight that ends in -278 is what I used.
 

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Discussion Starter #16
I'll pick up the clutch tomorrow night, put it on, and i'll post my results. I looked up the weights after i posted last, and i figured you had to be right. I have to go now, but i will post my results as soon as i can. Thank you for all of you help!
 

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Discussion Starter #17
Well, i got the clutch, and it looks like it should be rebuilt, and while i was there, i got a 21 tooth sprocket, and happened to find a set of twin pipes, all for the measly price of $30. I just put the pipes on and took it out for a rip, and whoa man did they make a difference. I'm unsure of the brand, they seem very large, and i had to take the hood off in order for them to fit, and the difference was so drastic i'm going to run with the hood off. It seems to be jetted just right, no airbox and twin pipes, and tune the 32mm carbs, this thing's an animal! now that i know the pipes work well, i'm going to re-do the suspension and the chaincase gear. By the way, is there anyplace i can get the spider assembly for the clutch for less than $100??
 

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Was the $100 price from your Arctic Cat dealer? Manufacturer's Supply has them for $40.99, and new rollers for $9.99 each (I just looked!). You want the big rollers for your sled. I see Dennis Kirk doesn't carry the hex bushings any more. Maybe surf the 'net to locate some or maybe you'll have to get them from your Cat dealer. The ramps, weights, and spring (green) will have to come from your dealer. If you figure out what kind of pipes you've got, let me know, will ya? I remember the HPE pipes for a 5000 Tiger used a 6000 muffler, if that helps any. It seems like Decker and PSI both made pipes for these sleds once upon a time, too.

It sounds like you're well on your way. Yer makin' me jealous as hell, though :drool: !

Where are you located, anyhow? Probably too far away come and see you run. Keep me posted on your progress.
 

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Discussion Starter #19
I forgot all about MFG supply.. that price was from the sled yard that i got the parts from, so i'm sure it was right from cat. I'll have to put the order in for all of my clutch parts, allthough i'm debating running the comet, i have it clutched to just over 7000 rpm, and the pipes make it really move, however it's still doggy off the line, it doesn't quite lift the ski's off the line, but after a few feet, they are pointing hi in the sky!! especially after moving the mount bolts lower!! I have got absolutly no idea on the make of the pipes, but they're big, and loud! It's simply written on them like 80' tigre or something, and man do they help that sled run! I didn't find the silencer to fit them, but it looks like it would use a 6000 muffler. (i got the 2-1 y-pipe too)

I'll be running at the local swap meet here in a couple weeks, i'm unsure of the date, but i'll find out. I'm located in southern MN so i don't know how bad you want to come see it haha. I'll have my sister take some digital photos if i can, and maybe see if i can figure out how to post them for ya. The sled won't have a hood on it, unless i take my spare and cut some reliefs for the pipes in the hood, I had to fab up my own flange setup, and they don't quite fit under the hood!!

What rollers do i order for my sled?? 03-148 or 03-149?

One things for sure... this sled is now faster than my newer 600, and i can't wait to whup up on my friends 600 poolaris! wtslap
 

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If your pipes have a 2-into1 on the stinger end then they're more than likely HPE pipes. Are they kind of made in two halves and then crimped together? If so, they've almost gotta be HPE pipes. I know their pipes hooked into a stock 6000 can muffler, that's probably why they're so loud without it. I always heard they were the best for a 5000 Tiger. But they should fit under the hood if that's the case.

Do you have the stock 45 degree helix? Try putting that back on and see if that gets rid of your bog off the line. That's why I ground the 45 degree angle on my 48 degree helix. I needed 45 off the line, and 48 once I got under motion.

As far as the rollers, you'll have to either call or e-mail them and ask them which one is the bigger diameter. The smaller one was about 3/8", and the bigger one was about 5/8". You need the bigger one.

Yer killin' me man! I WANT to see this sled run! Good luck smokin' your buddy!
 
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