YZ10 Works Projects

[stickboy007]

Two updates here:

'92 Works is mostly done. I ended up going with the Tamiya white springs, as I think it adds a nice look and is the same diameter as the original Yokomo springs (AE springs are slightly smaller diameter). I kept the gold aluminum steering rack, as it goes nicely with the gold ball joints, and subsequently inspired me to use gold shock shafts (AE TiN coated shafts). The AE shock shafts are a slightly larger diameter than the original Yokomo shock shafts, although the o-rings in the shock seal are exactly the same. The only difference is the guide bushings in the seals. They fit very tightly around the AE shafts, so you have to bore them out with a 3mm drill bit (I did this by hand. No Dremel) to make everything fit smoothly. I managed to make that fit reasonably smooth, although there is still a small amount of friction remaining. I didn't want to over-bore the guides and end up with the shocks leaking oil. Better to have it ever so slightly on the tight side for a shelfer (side note: the C-clips that hold the shock seals in are a major pain to get out, similar to the original AE shocks. I suppose I just don't have the right tweezers for the job, so this took me a lot longer than it should have). As for the steering rack, the spacing between the ball studs for the center link and the ball studs for the steering turnbuckles is pretty tight, and this limits your choice of ball cups. I used the stock Yokomo white ball cups for the center link and Lunsford ball cups for the steering turnbuckles, and there are no apparent binding issues there, but only just. Pink rims are brand new, as are the battery straps. I have a body and wing from my '91 Works that was already painted by the previous owner, and I think it would actually go pretty nicely on this '92. I have decals for a Williams FW-14 paint scheme, but that will just have to wait for another day. As for tires, I'm all out of original Yokomo tires, but I'm thinking Schumacher mini pins would go nicely here.

Having more or less finished the '92, I got started on the '93 runner. Pics below. I actually got further than the pictures before stopping for the evening (front arms are mounted). It turns out that one of the '93 runners that I bought had magnesium front and rear bulkheads. Maybe the previous owner tanked the original aluminum ones and got magnesium replacements? Luckily enough, one of the 870c's that I purchased came with an extra aluminum front bulkhead (aftermarket unit. The edges are sharper, the front profile has an angle, and the front tower mount "ears" are thinner than stock), while the other '93 Works (3rd car from page 2) had an aluminum rear bulkhead. So I am basically cannibalizing that other '93 Works to get what I need (bulkheads, hinge pins) to make the other '93 Works a more authentic build (with of course the exception of the Fibre-Lyte towers and top plate). The purple motor mount you see on there, some of you may have seen them on eBay a while back. I picked up two of them. They are, quite literally, **exactly** the same as the Suzuki motor mount, with the only difference being the anodizing color (purple vs. blue), and the considerably lower cost (I think they were $25 each). The only non-metric components on here are the inner camber link ball studs. This allows me to use RPM ball cups there, which hold tight yet can be easily twisted off to access the diff thrust bolt (the RPM ball cups seem to bind on the metric Yokomo ball studs, so I just used AE 0.3" ball studs for the inner camber link). All of the other white ball cups have aluminum ball ends, which I presume came from the YR4 lightweight parts set (I actually have one of those, but it's good that I don't need to use it here). I need to order some screws and other bits and bobs to finish this off (I want all hex screws here if it's going to be a runner...needs to be easily serviceable), but overall, I'm quite excited to have a '93 runner, and I no doubt count my blessings that I managed to source a '93 runner, and a '93 shelfer, and a NIB '93.

As for that "other" '93 Works...well...I'll figure out what to do with that. At the very least, it has a delrin front bulkhead, and I can just throw a magnesium rear bulkhead on it and make it some kind of hybrid runner. I'll deal with that later...

[hondaman]

Some very nice Yoke's as always.. I'm just so jealous.. Now sling some paint on that '92!!

Shawn

[stickboy007]

Just can't help myself

The '92 body is ready. I just need to clean it off and mount some tires. Coming soon...

'93 rolling chassis is almost done. Still working on the lipo trays.

[stickboy007]

'93 Works runner is done as a roller so far. Rather than type through everything, I figured I'd just post a video:

https://www.youtube.com/watch?v=jqUssFgME2c&feature=youtu.be
[youtube]jqUssFgME2c[/youtube]

Electronics are mostly installed (not shown here), although I do have to fiddle a bit with the ESC and wire positioning to get the body to fit smoothly over everything.

[Asso_man!]

Gotta love the '93 Works! What a luxury to run one, well done (video a bit too long )

[stickboy007]

Yeah, I did go a bit over time on that video. Wanted to make sure I didn't miss any details, though.

I managed to get the electronics installed and take it for a test run yesterday at the track. It feels different from the '94 and the 870c, so it took a bit of getting used to. One thing is for sure, though. All three of them corner like mad with that center one way pulley.

It appears that the weakest part of the chassis is the front steering knuckles. These nylon units tend to strip at the kingpin screw holes without too much effort, and I almost lost a beautiful aluminum kingpin on the track because of it. I think the solution is to just use a wider screw. I tried an AE 5/64 screw, which threaded much more tightly, but as it is not a kingpin, I need to find a way to pick up the slack between that screw and the hole it mounts through on the C-hub.

I think I might need thicker oil in the rear and to fiddle with the ride height a bit. I increased the static ride height to improve landings off of jumps, but it actually ended up traction rolling almost everywhere. Hopefully, I can get it sorted out over the next month or two in time for the VONATS. If not, then I may end up using my '94 YZ10 or CAT 2k as a backup.

[hondaman]

I noticed that when I looked at my 93.. the front knuckles do seem weak.. I know Rpm made a set with a metal threaded insert that would solve the problem.. hope you get it sorted out.. I want to see the video of it at the vonats..

Shawn

[stickboy007]

This should do it for the '92 Works. Not wanting to hunt for vintage Yokomo tires, i went with 2.2" Schumacher mini pins and they certainly look the part. The body and wing were painted and decal'ed by the previous owner, and just needed some cleaning. I decided to stick with this body rather than paint another one, since the pink on the body goes very nicely with the rims (the pink on the body comes out a little wonky in the photos, because I had to turn the camera contrast down a touch to keep the black stuff from washing everything else out...my camera phone is not very good).

Last one (for now ) is the Works hybrid. It's basically a hacked up '93. I'm about halfway through it and want to try and do a hex wheel conversion for it. It turns out that the universals I used for the '94 hex conversion (http://www.rc10talk.com/viewtopic.php?f=29&t=34196) actually have wheel axles which are too short for both the '94 and '93, so you end up with a lot of binding when you tighten the wheel nuts down. So I abandoned hexes on the '94 for now. Also, the DB01 front universal's dogbone is too long for the '93 front. So I'm back to square one on the post-870c hex conversion. I ordered a set of front/rear Hot Bodies D413 dogbones, which are 75/73mm, respectively. I think these should be the perfect length (let's just hope the ends aren't too big for the diff outdrives), and I just have to pair them up with long enough wheel axles, which I think I can pull from these other universals I bought that didn't work out for the '94 conversion.

@ Hondaman, yes, I figured out the fix to the front knuckles. if you remember those little brass sleeves that Tamiya makes for some of their screws (I can't seem to find a picture link at the moment...maybe I have the wrong name for the part. Brass tube? Screw tube? whatever...), you can take one of those and cut it in half with a dremel cutting wheel. It fits perfectly around an AE 5/64 screw and the half length is just about right for the depth of the kingpin holes in the C-hub, while the thickness of the sleeve is perfect for taking up the slack between the 5/64 screw and the kingpin hole. This is actually quite a similar approach to the '91 Works "kingpin" assembly, except here you're using a larger diameter screw to force a new thread into an otherwise stripped out steering knuckle.

[hondaman]

Thanks stickboy007.. I'll keep that mod in mind if I come across some more hub carriers.. I have one lone one left (I got 3 in a parts lot) so I'll see what I can do with that one.. I do have one idea.......

By the way the 92 looks clean.. Not a huge fan of the water oozy thing but it works on this one.. I'll give that one a pass...

Shawn

[flustorm99]

Very noice as usual. As for stripping your threads on your front knuckles, as mentioned before, i have used 4mm button heads screws of about 8mm in length(maybe longer cant remember) for the very same issue and i have had my 93 on a track used for running 1/8( have no choice) buggies and had no probs with the threads. The fit into the c hub is perfect with no movement at all. I have been slowly 'beefing' my 93 up for this track with ae factory turnbuckles(shoulda went lunsford but), some long rpm ball ends, 3-4mm carbon shock towers and i think i may try and whack a new plastic Traxas down force wing and wing stay for added strength for the rear shock tower for if and when it does flip...trying to bmax iii b44.2 it you could say. Got some SC10 shocks as well but havent tried them as yet.

[stickboy007]

Small update here...

I got some more track time in with the '93 Works runner. I can now see why the '93 WCS started using the turnbuckle for belt tension adjustment, because it also adds some structural integrity. If you just tighten down the two bulkhead cap screws and two motor mount screws to set the belt tension with the upper deck, at least with the glossy Fibre-Lyte parts, the washers will slip on the upper deck if you case a jump. Then your belt tension needs to be reset. Luckily, the FL upper deck comes with the hole pre-drilled for the turnbuckle option, and you just have to drill a hole in the rear bulkhead cap and then you're all set. It's a tight fit (would've been nice if the hole on the upper deck were a few mm further forward), but it works and should serve to help keep the upper deck from slipping against the washers under the mount screws. I will probably also end up shaving a bit of the upper deck that faces the slipper clutch. There is very little gap spacing there and I have already had the slipper hub bind against the upper deck once after a hard landing.

I think the more fundamental problem I have here is the shocks. The damping is way too light, and I'm using the smallest hole pistons that come with the RB5 shocks. It just smacks the ground on landings and, after enough times, the drivetrain binds due to the motor moving slightly or the slipper hub being shoved against the upper deck, or the belt tension comes loose due to the upper deck slipping. I could ghetto rig it and seal up one or more piston holes to get more pack, but I don't like the sound of that. I just ordered a set of SC10 rear and B44 front big bores, with V2 plastic shock caps (I'd rather break the caps than the towers). The SC10 rears have way more throw than the RB5 rears, naturally, plus the AE pistons cover a better range of pack than the Kyosho velvet pistons without resorting to 50wt oil. Should give me more tuning space for landing vs. cornering.

By the way, I am running the Turnigy Trackstar Turbo V2 ESC with a Trackstar 10.5T. ESC is very nice and the motor is very quick. Gearing is 81T/20T spur/pinion.

[hondaman]

The rear tower on the 93 W.C.S has the cutout for the turnbuckle, well actually it is the tower for the 94-up YZ-10's, and the Works 93 doesn't.. This allows the clearance for the system on it.. It is interesting to know this about the top deck shifting the tension though.. I bet it was a problem with the original buggy as well but it was far less of a problem as the finish wasn't glossy and the washers had something to "bite" into.. Since it does mount to 4 points I can see it being able to shift to hit the slipper.. There is a pretty tight tolerance there.. It wouldn't take too much to do that if the top deck went slightly askew..

Shawn

[flustorm99]

Doesnt the 93 have a centre post? How can tensioning with the rear bulkhead affect the tension of the front belt with the centre post? Doesnt make sense or am i missing something? Surely from the centre post forward is all u can tension? The hole in my topdeck for the post isnt oval so allows no movement once tightened? I noticed my front belt got a little lose but it was purely because i couldnt tension the topdeck to the front plastic bulkhead tight enough with the small screws. I put some larger screws in and this seems to help as i can tighten it more securely. If i am on the wrong track...please explain.....

[hondaman]

With the whole rear being adjustable that is where I am thinking the top deck is shifting ever so slightly.. The 4 points are at the two points at the bulkhead cap and the 2 points at the motor mount I was speaking of.. If those parts slip the rear bulkhead could shift the top deck a little which would be enough to hit the slipper and since there is a problem with dampening this just amplifies the problem of it being able to come loose.. At least that is my thought.. the top deck could possibly pivot on the front post.. there is a bit of chassis flex as well even if it 3mm.. But you bring up a good point flustorm99.. It should stay put but if it isn't, then what I have stated is my best guess.. He does have the post (red one) in there if I see correctly in the pictures.. The 94 has 2 posts IIRC.. maybe this was to help with this problem?

Shawn

[flustorm99]

Yeah mate i agree with what you say re the rear part pivoting etc and rubbing the spur..makes perfect sense, i was referencing stickies issue with the frint belt losening after a jump..and yes the 94 does ha e two posts and maybe your are right in that they were they to possibly fix this? I think one of the YZ spurts will no doubt be able to turn us onto the right answer...anyway mine seems to go ok touch wood...only thing that i am worried about is i only have one set of front sus arms and if one goes ping then i am stuffed...i do have some delrin ones (that one of the members here helped me out with) on my shelfer but thats it...hard babies to find ...