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So, it seems we all know that Kyosho Optima bumpers are few & far between on eBay or otherwise, unless you want to spend $100+ for a parts car with a bunged up unit. Back in the 80's I bought a couple aftermarket bumpers--I couldn't recall the maker--that at least fit quite well. They were red but I dyed one black and it looks great.

Considering there are so many Optimas/Turbo Optimas/Salutes/Javelins out there, it seems hard to believe that so many of us are driving around bumperless. There's gotta be alternatives, or something that you've modified to work in place of the stock bumper.

Please share your ideas! I need a few bumpers and can't justify the $50-plus to buy the stock one. Thanks!

whats the mounting look like? do you have any skills at fabricating?

If so, you can pick up some kydex, cut it, drill it, and dip it in boiling water to form it as you need.

jwscab wrote:whats the mounting look like? do you have any skills at fabricating?

If so, you can pick up some kydex, cut it, drill it, and dip it in boiling water to form it as you need.

For a half-dozen or so years, I did a lot of custom computer cases, back long before it became mainstream to just buy a computer case with a window and LED fan already preinstalled, and that involved a ton of fabrication with plastic, acrylic, aluminum...but I don't even know what kind of material these Optima bumpers are made of (or something similar, anyway). Kydex? Never heard of it, off to Google I go. The basic bumper shape is quite simple. It's basically a T shape with 3 mounting points, notches cut to allow a pair of screws to bolt onto the frame rails, and a rectangular hole allowing the curved bulge of the front skid-plate to fit flush. It has only one bend.

JG made some Kydex varieties, and there is no reason you can't. Let me see if I can google up a pic..

Y'ernat Al wrote:JG made some Kydex varieties, and there is no reason you can't. Let me see if I can google up a pic..

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Y'ernat Al, that looks to be the exact aftermarket bumpers I bought, way back in the 80's! They were butt-ugly red in color and had a grained texture. I trimmed mine down too, though not so much as yours...I wanted a little of front wheel/arm protection, but I remember the original extending out past the tires.

Those JG units also install a bit differently, using 4 frame-rail holes that are also used for adjusting chain tension, instead of the two outer holes and single front bolt. The quality isn't very good, to be honest, but it's better than nothing.

kydex is cheap. it cuts alot like abs, but slicker, kinda waxy. usually black and smooth on one side, textured on the other. most aftermarket bumpers that look like flat sheet are kydex.

it has a low melting point, and can be bent cold for simple bends, or put in boiling water or low 200 degree oven to shape around radii, or whatever.

mcmaster sells it in various shapes, I think I got a 12" x 12" sheet for like.....10 bucks in 1/8" thickness.

if you have cut plastics before, give it a go, I think you'll be able to turn out something you will like.

i grabbed one of these . the seller said he made like 12 of them...


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bdrmbully wrote:i grabbed one of these . the seller said he made like 12 of them...

I've seen a few aftermarket aluminum bumpers for various cars online. For a runner, is it a good idea? If you have something up front that's more rigid and far less flexible than the original bumper, something's gotta give somewhere else...I'm thinking machine screws tearing out of the aluminum rails, for example.

this is my optima with GPM mid-motor conversion.........I cut out part of the nose plate........throw away the U-frame (this is only used to attach the anti-roll bar which I think is useless)........ attach a mini bumper to it........looks neat & tidy......

minimini wrote:this is my optima with GPM mid-motor conversion.........I cut out part of the nose plate........throw away the U-frame (this is only used to attach the anti-roll bar which I think is useless)........ attach a mini bumper to it........looks neat & tidy......

It appears that many offroad cars these days have those small chin bumpers...I wonder, was it just determined that protecting the suspension arms & wheels with a wide T-bumper wasn't working or effective anymore? It seems to me that the T would flex during a collision with a curb or something and bear the brunt of the crash, protecting (or at least deflecting the impact force from) the wheels & front end.

Or maybe moving to those tiny chin bumpers was a racing thing in order to reduce weight? Just wondering.

I think it's a matter of racing, the fact that the full width bumpers could tangle with another racer and cause problems. you can get another car's suspension wedged between the back of the bumper and your front suspension. then a turn marshall has no choice but to give them a yank apart......

with a small chin bumper, full straight on imacts are lessened, and you take the chance that you can just drive over your opponent

Makes sense--I wasn't even thinking about the greater potential for tangling with competitors. Good point! For the basher though, it seems those chin bumpers are not terribly effective as a form of crash protection, then.