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Great cars - I love them all!

It's so cool to see the old classics out getting down and dirty, too, not just sitting on a shelf.

I had been searching the net for photos of how the Torque limiting clutch installed and couldn't find any, so now I have it already, thought I post a pic of the clutch pinion installed, pardon me for the broken gear cover I think this 1 is made of steel as I have another which look like it's made of alloy. I intend to try running with mamba max pro 6900 and see how it handles , i inserted 3 O rings for maximum clutch engagement as it gets very hot if I only install 1 O ring.

What motor are you planning to run with that, are you going brushless?

I wonder how that clutch pinion works...are you also using the Turbo Optima/Salute torque limiter (center gear with spring on the shaft as opposed to a solid shaft)?

I think i have a install paper for the clutch pinion setup, Ill look when i get home.

Currently the black motor is a team power stock motor, which is similar to tamiya sport tune. I intend to use Mamba Max Pro 6900 BL motor,I think its way overkill for such an old car, but I'm just curious on how Optima will handle such power. I'm using the original optima solid shaft center gear. Got a belt system as standby in case the chain system gone kaput. if the 6900 is way overkill I'll just change to a Lehner 4200 motor. By the way, anyone here has a hardened final pinion for sale? I reckon I'll need it if I'm to run on brushless for long term. I'm currently running Pargu's alloy final pinion.

kaz_z wrote:Got a belt system as standby in case the chain system gone kaput. By the way, anyone here has a hardened final pinion for sale? I reckon I'll need it if I'm to run on brushless for long term. I'm currently running Pargu's alloy final pinion.

I might have one up for grabs, along with several nice Gold Celebration chassis parts, and a ton of excellent-quality Optima metal & plastic parts, but I'm in search of a belt drive system in trade. Tracking down hard final pinions at good prices is like finding a needle in a haystack--you better search high and low, need a lot of time and patience, and even more luck.

[quote="kaz_z"]I intend to use Mamba Max Pro 6900 BL motor,I think its way overkill for such an old car, but I'm just curious on how Optima will handle such power.quote]
That is waaay too much power for an old Kyosho chain drive! You're looking at over 50,000 rpm with a 7.2v/7.4v battery. A 6900kv motor is roughly equivalent to a 5.5t motor. I'm not sure I'd want to go much hotter than a 13.5 with the stock chain drive. A 17.5 might be even safer.

tsan wrote:That is waaay too much power for an old Kyosho chain drive! You're looking at over 50,000 rpm with a 7.2v/7.4v battery. A 6900kv motor is roughly equivalent to a 5.5t motor. I'm not sure I'd want to go much hotter than a 13.5 with the stock chain drive. A 17.5 might be even safer.

I was kinda thinking the same thing. I have a mystery black can brushed motor that appears to be a 14T in my Zebra Turbo Optima (chain drive) and it's ridiculously fast on 8.4V. Even accounting for my decayed driving skillz, I can't really imagine needing to go any faster.

EDIT: For comparison's sake, the Le Mans 240SB was one of the hottest motors at the time, and was rated at around 30,000 rpm. Packing nearly twice that much power is maybe not such a wise venture.

yes i know it's probably a bad idea to use the 6900, but heck i'm very curious on how optima can handle it , perhaps i'll just run a pack or 2 to see how it holds up,not going to torture it the whole day. the 240sb is one fast motor but has to be geared low , i tried gearing it at 14t and it lacks the torque to go fast , at 12t it seems faster than 14t.

kaz_z wrote:yes i know it's probably a bad idea to use the 6900, but heck i'm very curious on how optima can handle it , perhaps i'll just run a pack or 2 to see how it holds up,not going to torture it the whole day. the 240sb is one fast motor but has to be geared low , i tried gearing it at 14t and it lacks the torque to go fast , at 12t it seems faster than 14t.

Re; 240SB gearing...yes, you need ideally a 8T to 11T pinion for that motor. If you're keeping all the rest of your stock gearing, I'm not sure what you'll do with an even more torquey, powerful motor...a 5T pinion? I believe you'd have to change your spur gear to something more modern if you want a motor that fast & powerful to work properly. I'm not an expert in that area, but logically that seems to be the case.

fix the broken gear cover with plastic bottle cap, hope it'll hold up .

I don't think that'll hold, and once dust & dirt gets into that black tape, it'll fall off...and might make a mess if it unravels and gets caught up in your outdrives/dog-bones.

didn't have a chance to test at track, it's very wet due to heavy rain last night , tested on road , it just flip ha ha , wild willy had to throttle very slowly , the clutch engage very quickly even with 2 O rings , before i can test with 1 ring, it rain again

Optima Hard final pinion vs normal final pinion, what surprise me was the hard one actually weights the same as the normal alloy, at 6g. My buddy has an after market one, which I think is made of steel, weights so much heavier, so I guess kyosho's hard final is some kind of coated/anodized?

Yeah, the Kyosho one must be hard-anodized...I have 3 hard pinions and they're all noticeably heavier than the Kyosho one, and they are colored a lot darker, almost a charcoal grey color instead of bright aluminum.