I finally got a camera that takes good pics, so Im gonna share some valuable info on one of my favorite chassis, the Tyco Curvehugger.

Whats funny is, the names 'Curvehugger' and HP-2 have been put on the packages of 3 chassis that are very different and have 2 sub variations totalling 5 recognizable versions. All motors arent created equal either. So before we get to the mods, lets ID what you have:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00114.jpg

None of these is bone stock, but just the same, from the top view, only the black colors can be distinguished from the silver except of course for the one at the top. I refer to all 4 styles at the bottom as 'curvehuggers' and the style at the top as the 'HP-2' even though I once saw an exploded diagram on Ebay referring to this chassis as an HP-3. Its VERY different from the CH in every way except for the pickup assembly. Still, the tips Im going to cover here will apply to any of them.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00115.jpg

From the bottom you can see the differences. I have them lined up left to right based on which I think came first: A: Black chassis, quad flux collectors, B: Black chassis, dual flux collectors C: grey chassis dual flux collectors closed crown gear box D: grey chassis, dual flux collectors open crown gear box and finally E: HP-2 with a radically different design incorporating separate traction magnets, redesigned motor and rear gearset, and it could have either the same aluminum pin as the CH, or a new a guide flag.

Outside of the color and the open vs. closed crown gear box, B-D are nearly identical. A of course has with its wide flux collectors has nowhere near the magnetic downforce and slides around much more. In MY opinion, this is the best of the bunch for challenging racing since you can slide the rear out in the turns and it takes much more skill to drive, having greater acceleration (if you have the right motor; more to come on that) than an AFX magnatraction but about the same magnetic traction. Trouble is, the black plastic can be more brittle than the grey.

There are 3 distinct motors used in the CH series also. And of course they are NOT created equal:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00113.jpg

The one on the far left is a Johnson motor and these are used on the first CH chassis (black, quad flux collectors). Its the weakest of all of these, if you have one of the other 2 to swap in, then go for it. The motor in the center is also a Johnson, but has an improved magnet/box design. since the mags clamp in, theyre lined up nicely as opposed to the glued in design of the first, which is probably why theyre much weaker. This is a good one, and these can run very strong. The one to the far right is a Mabuchi and this is probably the best of the bunch. Personally, Ive swapped these green arms into the 2nd style johnson box/mags with some pretty impressive results. And feel free to experiment with arms from other chassis too: TycoPro, Aurora G+ and Tyco 440 X2 arms all can give good results in either Johnson box #2 or the mabuchi box.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00116.jpg

The HP-2 has 2 motor variations: A johnson motor like on the left which should look familiar. It has the same lousy glued in motor magnets as the 1st CH design and while it runs better than that one, it gets dusted by the green wire Mabuchi design to the right. The Johnson arms on these arent bad though and if swapped into the Mabuchi set up it will run fairly well. Note the pinion gears in this pic also. The white one mounted to the Johnson is the stock piece and like most every one Ive ever seen its cracked. The mabuchi shows the first upgrade you should make: Stock pinion from a tyco 440 or HP-7.

Next post will explain how I mod the motors on these.

The first mod you'll make to the motor is venting the endbell, which has been seen on several of my other pics. This doesnt occur stock, you must carefully take a razor blade or dremel and remove some material exposing the commutator and brushes. This allows soot to escape, promotes cooling, makes cleaning easier and allows you to see how your motor is running.

Completely disassemble the motor. I like to soak it in rubbing alcohol at least a few minutes to loosen up any crud. Be careful not to lose the little space disks that can be on both ends of the armature. I use a rubber emery wheel in my dremel to polish up the commutator nice and true and get rid of any soot. I also scrub the brushes all around on a piece of paper to polish them, dip a piece of poster putty in the alcohol and carefully roll the springs on it to clean off the soot. I then take a clean toothpick, stick it into the barrels and turn the barrels on it, polishing the insides. I then jam the barrel nice and tight onto the toothpick, and take my dremel/emery wheel and turn the barrel against the spinning wheel, polishing all sides nice and bright.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00075.jpg

Here is a stock endbell with the part you'll remove marked with blue sharpie. You could do this from just one side, but best to do both. I use a sliding razor scraper to open these up, but you have to be careful! Ive put many a slice into my thumb or forefinger doing thise.


http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00077.jpg

Once you mod the endbell reassemble the motor, oil the bushings up and this is what you should get. Your motor should spin like mad, and will run cooler and cleaner to boot.

Now, to mod that pickup assembly...

The pickup assembly is definitely the weak spot of the CH/HP-2 design. But it does have its strong points, if you just unlock the potential. There are 3 variations on this part also:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00100.jpg

The 2 assemblies at the top are identical to each other except color. Those brass 'rivets' on top of the assemblies are actualy sleeves in the pickup spring 'buckets' , as opposed to the lower 'flat top' design found on later CH's and all HP-2s which have a fully plastic 'bucket'. If you are keeping the stock pickup ski/spring setup as opposed to doing a braid conversion (Ill show that mod another time) then the brass rivet design is the best one to have. The sleeve going all the way thru means more metal-to-metal contact with the pickup springs which is good, since the pickups just free-float with the only electrical connection being the spring. An underside shot shows the difference:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00101.jpg

One problem with most of the black pickup assemblies (besides being more brittle) is that the pickup springs on a lot of these are made of steel, and dont conduct as well as the copper springs. Ditch em for copper. Tyco motorcycle springs are still available NOS and are a perfect replacement! The other problem with this design is, the pickups dont retract far enough, meaning either they grind the track creating drag and slowing you down while also creating more wear on the pickups. OR, you have to run huge front tires. Not good. But also fixable with my mod, which to date Ive done on every single CH and HP-2 I own since developing it several years ago. Ive done it easily over 100 times so I can do it in under 5 mins. Here's how its done:

First, carefully compress the rear 'hook' of the pickup skis and pull them down and hook them out of the assembly. Be careful not to drop the springs. Carefully re-open the rear hooks with a small flat blade, but not too far. They break off easily. Now, flip the assembly upside down. Steps 1 and 2 only apply to the newer, 'flat top' assemblies:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00111.jpg

The stock part is on the left, step one is done on the right. See that front brass tab sticking up? Thats part of why your ski wont retract. Bend it down with a screwdriver flat towards the bucket.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00103.jpg

Now step 2 involves using a razor blade to rough out the excess material on the bottom of the spring buckets. Again, this wont work on the rivet top assemblies since the brass sleeve goes all the way thru.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00106.jpg

Go right to the insides of the bucket, and use a sawing motion to trim thru the backside of the buckets. This way when you shave them off, theyll come free as you come to your cut and it'll be a much neater cut.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00107.jpg

This is a spot where you REALLY have to watch your thumbs because of how you have to hold the assembly. Use a good sharp blade and shave that ring of excess bucket right off. This will rough out your assembly and you'll be ready to file it smooth.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00108.jpg

Next take a square needle file and get right to the inside of the buckets and file it down against those ridges that run to the inside. File it down nice and even with the rest of the pickup assembly. Again, if youre using a rivet type assembly then this is step 1 after dismantling it.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00108.jpg

Once youve done both sides with the square file, you should have a distinct cut on the insides of the buckets. Then take a flat or equalling file and go over the whole thing. It should be uniformly flat, with no traces of the bucket, or the brass tabs protruding beyond the underside of the assembly.

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00110.jpg

Once youre done, you should see that you took out a good bit of material. Here is a pic of a stock part on the left, with the cut and filed part on the right:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00112.jpg

Next step is flattening the pickup skis if theyre not completely toast. They have 2 upward bends, one on each end. You want to get the ski pretty flat so it gets more track contact and so it fully retracts. Put it in a pair of flat nose pliers and flatten the surface of the ski. Youll see the ends spread out as you do, so squeeze up near each end good and tight, the press the ends back upright. Do that on each side, otherwise the ends will have spread too far to fit into the assembly. A fully filed down rivet assembly is shown above a stock pickup on the bottom left, flattened pickup on the right:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00080.jpg

Get out your dremel and polish ever bit of metal thats going to do any conducting. Again, the rubber emery wheel is king here. Get both sides of the pickup skis, both ends of the springs, top and bottom of the assembly tabs that meet the motor brush barrels, and get the insides of the spring buckets. You can use a little polishing compound in there, and chuck a toothpick into your dremel to get right in the edges of the brass buckets since thats where the springs meet them. The difference between a car with a fully polished pickup assembly and a halfass polished pickup assembly is HUGE. Once you put this all back together, the differences in how the pickups retract is amazing, even though you only removed a small amount of material. Here's the comparison:

Stock, unmodified pickup assembly with ski at full compression:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00083.jpg

And here's the modded part at full compression:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00085.jpg

From the inside angle:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00086.jpg

In terms of how much smoother, faster, and quieter your car runs you'll be completely amazed. Your pickups with last MUCH longer since in stock trim the front tires wont even touch the track. Now they can support the front of your car. And with the motor mods and full on cleaning you just did your CH should be running like a total madman!

The other mods I do are replacing the stock aluminum guide pin with a leftover AW/JL XTraction piece turned to the pin side. The aluminum piece is probably already worn to paper thin as it is. I generally swap out the rear axle with a tyco 440 piece since its knurled to grip the crown gear and slightly wider. If youre keeping the stock wheels (hopefully you have a set of the centerline types in grey like came on the early black CH chassis) then the rear track is now slightly wider. And those wheels work beautifully with stock XTraction rear tires. AJ's delrin rear hubs work very nicely as well, or you could always do like my pic shows and go to Lifelike wheels which update the look, give you some width and fix the track problem as well:

http://i77.photobucket.com/albums/j71/grungerockjeeper/Curvehugger%20101/DSC00087.jpg

Wow, Grungemeister, this thread is looking pretty sano! Now I have something else to add to my "to-do" list. Thanks for sharing the sweet tips!

Great job on the "how to". I didn't know beans about tuning up a Tyco CH, much less which chassis to look for. Thanks. TomH

No prob guys. Ive been doing this same mod for at least 5 years, but I just recently got my carcass to Best Buy and got a good camera. Ill be showing my braid conversion for the CH/HP2 and also a few mods for the HP-7 soon.

cool deal, I am in the middle of building a routed track, (now, if I can just get the grass to DIE!) The braid conversion would be right up my alley for sure. I Googled around a bit. Is that Mabuchi motor in the CH a HT-50?

What a great read and excellently assembled tute Jeeper!

So my clunker CH's arent just rail grinders after all????

Enjoyed your new camera work and concise text. Thanks for taking the time!

Wow.... Great stuff! Thanks for giving me yet another project to work on. ;)

Well done!

Marty

TomH--I dont know what the designation on that mabuchi motor is. I do know that the magnets are stronger, the arms are different, and the HT-50 will snap into the chassis (the bulkhead bushings are the same size, unlike on the HP-2 which are larger) but it doesnt have the cutouts in the motor box for the flux collectors. Ill be showing off the braid conversion soon. It builds on the pickup assembly mods shown here, and its pretty idiot simple from there. Hell, its even reversible to the ski setup if you want.

Bill, youre right these definitely have a lot of untapped potential. Thats the reason for the whole thread is so these cars can be raced and enjoyed the way they were meant to be.

:thumbsup::thumbsup::thumbsup:

Thanks a lot for that superb, illustrated write-up!!!

I always liked most of my HP2 TYCOs, but never really knew (nor cared) why some of them run better than others. Now I not only know what to look out for in the future, but also what one can DO to them...!!!

Thankful greetings from Germany,

Claus

Excellent tutorial Grunge!! I have a couple of these chassis that won't run right... The mystery has been solved, and a few modifications have been added to my to do list!! Thank you!!!! :thumbsup::thumbsup::thumbsup::thumbsup:

Thanks for posting all the info. This is the first thread in the Tuning Tips section that I have enjoyed.
hojoe

glad you guys are picking up a few things, sharing discoveries is the whole point of this thread. Soon as I score a virgin HP-7 or 2 (all mine are modded) Ill share some tips on those too. Again, my braided pickup conversion tutorial is coming....

WOW!! you should write a book on all Tyco's chassis!! I am gonna re read it again when i get back from vacation! Just freakin awesome and I cant wait to try it! i do have alot of hp2, hp7 and ch chassis !!

Wes

I have a process for HP-7s too. Its not nearly as involved but soon as I get a few more untouched pieces in hand Ill be posting on those too.

What a great tuning thread! I always new these cars had potential, but no one ever knew what the heck they were looking at. When we tried racing them, all we knew was that some ran so much better than others that it wouldnt be fair to have a race class of CHs. Now I know.

Rich :thumbsup:

grunge,

Your new camera and this thread are great! Will have to try this on a few of my Tyco Chassis sitting in the wings waiting for some Dawgs.

Bob...very usefull information (Thank you!)...zilla-

Another question for you grunge... where do you get the mabuchi upgrade motors? Also, have you seen this guys stuff, just wondering if it's any good or not?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=220434352502

I hadn't heard of racers edge stuff before, wondering if this might be a way to go as well.

I found I had 4 of the original HP-2's with the green wire arms, so maybe they aren't a total loss, but I am wanting to give them the "treatment", I need something to do. :)

Thanks again for the great articles!

Marty

No worries, Marty. Nothing like sharing a hot tip on something like this and seeing it work for others like it does for me. Mabuchi motors come in a lot of CH/HP2s right from tyco. You just have to get lucky, although theyre pretty common. I bought a racers edge redwire HT-50 motor to put into a Riggen repro chassis and it runs nice and smooth, his zapped magnets do put out a bit more torque. Im sure he could work up a couple CH motors for you though, the HT-50 tycopro style motor isnt THAT different from whats in the CH.

So the guy, that I linked on ebay is the racers edge dude? Or do you have a link to a website for this guy?

I did the work up on one of these cars and it picked up about .5 seconds on a lap. pretty cool stuff. I have to admit I had no idea how much fun these cars are!

Thanks again,

Marty

dunno if he has a website or not, but he is on the 'bay a lot.

I think the racer's edge guy used to have his own site but he only has the ebay listing now. I have bought from him and he is on my great to deal with list. He has a way of getting more out of a Tyco Pro than I thought possible.

Russ the Hutt

Good to know, thanks Russ!

This thread, the one grunge just did on the braided pick ups and the fray car thread NEED to be stickied!

Too much good info in here, this has given me yet another car to play with darn it!

This thread is brought to you in part by...

http://www.rodfarquhar.co.uk/downloads/stp_logo.png
The racers edge.

I mainly drag race my cars. My question is are the newer gears better than older ones for dragging. I remember years ago Tyco had a hop up kit of sorts for racing.

Another late thanks for this thread. I have a bunch of these chassis, mostly under Camaros and Trans Ams, and they could all benefit from this wisdom... and I plan to use the info in the HP-7 thread also. very well done tutorials!

--rick

Thanks to all for this post!!!More help for me!!ENTER TYCO!!

This forum rocks!

Grunge, Thanks for sharing a Great Tutorial!! Have to work on these chassis which only considered as collector mounts! Keep the how to's coming, always appreciate learning new techniques. ..RL

just scored some tycos for free from my afx buddy.it's really nice knowing he likes to unload all his unwanted tyco stuff on me!sigh...a good friend indeed.when i get some better light and magnification i want to try these mods.i have the quad flux chassis,and they slide great.especially the one with no mags!
oh and one more thing!all the tycos he has traded me so far had the white boots on them!

Hey Newbie, if you have some curvehugger chassis to experiment with, be sure to check out this thread: http://www.hobbytalk.com/bbs1/showthread.php?t=257624 Wait till you see how these chassis run after you do this conversion!

Bumpin this thread up cause I'm fixin to use it.

Can this mod be done on the HP 7 as well ?

Gonzo

man this is interesting! the grunger really has it down. after reading this many times i,ve decieded to look for and bid on some curve hugger on ebay i also started looking for replcaement skis/shoes but it looks like they mmight be hard to locate.see what you did tex now i gotta change gears and try some new stuff. i did check out the superbird body for this type of car could look pretty cool flyin down the back strech on my trak. now i,m screwed!

I'm new here, and a little late to this thread, but it's Brilliant ! :thumbsup
Kudos to the OP....ahhh- do they have a Kudos Button on this forum :D