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  View original topic: Recommend me a decent pedal set or solution.
Aerindel Sun Jul 26, 2020 2:11 pm

Its been a long time since I've posted and the bug out buggy as pretty much just been sitting under a tarp in the woods.

Anyway, the tarp blew off it yesterday and I thought I would get it out and run it around a little. Was having a little too much fun and I found myself heading into a dirt bank going too fast. I stomped on the brake, locked up the wheels and then because it wasn't stoping....kept pushing on that brake pedal as if that would make it stop faster.

This did not stop me from crashing into the dirt bank (no damage) but it result in the rod to my brake MC folding up like it was made out of wax and the pedal twisting.

This is the SECOND time this has happened to me.

My pedal set is a 'Latest rage' one (I think, its not marked) that I inherited with the buggy frame when it was all given to me. Aside from the crumpling up issue, the piston also don't fully extend, they just push back as far as they have to under hydraulic pressure which leaves about an inch of free travel in both pedals which seems non-ideal to me. (you've probably forgotten but I don't actually know what I'm doing, I just do it anyway) Brake and clutch work find but they feel like crap and of course I don't think I should be able to destroy the pedal and push rod just by panic braking.

Anyway....does anyone have a recommendation for a decent pedal set that doesn't break the bank? Or someway to fix mine? I've been thinking it wouldn't be hard to replace that push rod with a grade 8 bolt but that still wouldn't do anything about the pistons not fulling extending....unless that is normal..?




dustymojave Sun Jul 26, 2020 6:39 pm

1. So what stops the pedal from coming back toward the driver?

2. The pushrod length is adjustable. But it looks like (based on the location of the nut) the pushrod was all the way in. But it also looks like the nut was not against the pedal arm pivot. It wouldn't bend there if the nut were there. It would bend on the other side of the nut. The brake pedal should have 1/4-1/2" play before the pushrod starts pushing the piston in the master cylinder.

3. When you're going into a bank or a big hole or whatever, it's best to back off the brake. I had a head-on crash 15 years ago. My right foot was on the brake when we hit (at 55mph, I only skid the length of the truck before we hit.) I wound up with a serious sprain. Lucky, considering the brake booster pushed the back of the hood up 4". But knowing when to take my foot off the brake pedal was a factor in my winning a championship in my race buggy. Even though I didn't take it off when I should have years later in the crash.

Aerindel Sun Jul 26, 2020 8:25 pm

The pushrod was all the way out in an attempt to take up slack

The nut was backed all the way out, not tightened against the U nut or whatever its called on the end that attaches to the pedal.

Even with the pushrod all the way out there is still about an inch of free pedal before it contacts the piston.

The pedal is stopped in the outward direction a washer retained with a C clip in the MC. The washer stops the ball end of the push rod from pulling all the way out of the MC. Which is why backing the pushrod all the way out of the pedal didn't actually fix the problem as the play was between the pushrod end and the piston.

I 'think' there is a spring inside the MC that is supposed to keep the piston all the way extended, trapping the pushrod end against it so there is no free play, but I think the piston is sticking enough to keep it from extending any further than it has to to release the brakes.

I may just need to rebuild the MC but I am not impressed as there are only about 600 miles on it.

#3...noted. I will hopefully be able to get out of the habit of just mashing on the brake when I think I'm about to hit something. Luckily I was probably down to 10 MPH when I hit the bank and just bounced off...except for bending my pushrod and brake pedal with my own foot.

SamT Mon Jul 27, 2020 5:34 am

Iíve had a lot better luck with buying wilwood stuff from speedway.

Dale M. Mon Jul 27, 2020 7:34 am

How good are the wheel cylinders and brake pads/shoes... All the pedal pressure in the world at MC can not stop you if there is a fubar at wheels...

Also once brakes lock up wheels, you are out of control... Brake pedal pressure means nothing after that point... Yes I know its human to press harder on pedal to stop faster, but at some point all effort is futile, and results is going to happen no matter what....

See two things here, bad mechanical issues at brake pedal, and driver.... Yes I know you are just like the rest of us, the best driver in the world... That is why almost all new vehicles come with anti lock brakes... Yes I have a story to tell about brakes but its to long and unimportant for issue at hand...

Dale

jsturtlebuggy Mon Jul 27, 2020 1:25 pm

Yes the pistons in the master cylinders have a spring in the to return the pistons. It they are not returning and you have large gap between the pushrod and piston, like you think they are not returning.
Most of the cheap master cylinders are just aluminum bores and wear out, not rebuildable.
Since CNC is now out of business finding a good replacement would be a Wilwood or JAMAR brand.
You can find the Wilwood at Speedway Motors and KarTek. One dealer for JAMAR is KarTek.

And if buggy sits outside during winter, it not doing it any good for the hydraulic system.

Aerindel Mon Jul 27, 2020 1:53 pm

Quote: How good are the wheel cylinders and brake pads/shoes... All the pedal pressure in the world at MC can not stop you if there is a fubar at wheels...


They are almost new. They work perfectly. The wheels locked. I just kept pushing because that was what I did in the second between when I realized I wasn't making the corner and when I hit the dirt bank.

Stopping was not the problem, well, it was MY problem but not a mechanical problem :)

The problem was I bent my pedal. I do not think a pedal should be so weak that you can break it by pressing on it, regardless of wether that was the what I should have done.

I have no problem with braking. The brakes work as well as they possible could. But the pedal set itself seems badly made and easily broken. I do not think my legs are inhumanly strong.

Quote: See two things here, bad mechanical issues at brake pedal, and driver.... Yes I know you are just like the rest of us, the best driver in the world... That is why almost all new vehicles come with anti lock brakes... Yes I have a story to tell about brakes but its to long and unimportant for issue at hand...


Eh....anti-lock brakes are a scam. They increase braking distance....and on snow, sand, gravel, etc....can GREATLY increase braking distance. Almost doubling it in those cases. Statistically, they even result in more deaths.

I learned that the hard way that I need to disable the anti-lock brakes on my modern vehicles in the winter to have any control over them on my road. Until last winter my truck was a 93 toyota without ABS...then I upgraded to a 2000 with them and the first time down the road in the snow almost resulted in needing new underwear. I. Simple. Couldn't. Stop. It was like one of those nightmares where you go to press on the brakes and nothing happens....except in this case what happened is the pedal buzzed under my foot and the truck just kept going down the hill no matter what I did.

Now, they may have some benefit, at high speed, on dry pavement...but I that isn't were I ever really need brakes. When I need brakes to really work is usually at about 20 MPH on a bad dirt road, with snow, a situation where ABS will do everything it can to kill you.

Quote: Yes the pistons in the master cylinders have a spring in the to return the pistons. It they are not returning and you have large gap between the pushrod and piston, like you think they are not returning.
Most of the cheap master cylinders are just aluminum bores and wear out, not rebuildable.
Since CNC is now out of business finding a good replacement would be a Wilwood or JAMAR brand.
You can find the Wilwood at Speedway Motors and KarTek. One dealer for JAMAR is KarTek.

And if buggy sits outside during winter, it not doing it any good for the hydraulic system.



Thanks. I think that is exactly what is happening. And yes, it sits tarped outside in the winter.

Last night I removed the MC, took out the piston, cleaned and greased it and now it moves all the way out under its internal spring pressure. I'm going to fabricate a new pushrod from a grade 8 bolt for now while I shop for a better pedal set.

At least my cutting brakes are CNC. They where in the random box of dune buggy parts I started with and totally siezed but I got a rebuild kit for them and fix them.

dustymojave Mon Jul 27, 2020 6:25 pm

The master cylinder piston not returning was a problem.

Bending the pushrod under impact is NOT. In the crash I told you of before, the master cylinder pushrod, the pedal arm, the master cylinder mounting to the firewall, All bent. The pushrod bent as a direct result of your impact into the bank with the brake pedal under hard pressure. I presume the pedal arm itself also bent.

I've seen it many times in many race car crashes. It was once my responsibility to inspect race cars after crashes. I also drove a tow truck for a time while in college. Saw a number of damaged brake pedals and linkages in the cars I towed away from crashes.

That doesn't mean the pedal, pushrod and master cylinder and such were faulty.

A grade 8 bolt will work fine. Just round the head to match the head of the old rod.

I HAVE TO agree with comments above about ABS. ESPECIALLY in questionable traction. It virtually disables ALL braking ability on loose dirt or ice. The foot of an experienced and competent driver has vastly more control of braking than ANY ABS system I've ever encountered.

Aerindel Tue Jul 28, 2020 3:08 am

Quote: Bending the pushrod under impact is NOT. In the crash I told you of before, the master cylinder pushrod, the pedal arm, the master cylinder mounting to the firewall, All bent. The pushrod bent as a direct result of your impact into the bank with the brake pedal under hard pressure. I presume the pedal arm itself also bent.


Yes, the pedal arm also bent.

Perhaps it was the crash although 'crash' is really overstating it. It was more a "oh **** that corner is sharper than I thought....skidddd....bump"

I can't be positive, but I'm pretty sure the pedal folded up before I actually hit the dirt. Anyway, I've never really been impressed with the pedal set in general. It has always felt cheap and loose. Its not what I would have bought if I had been the one to get it but like I said, it was free, so I used it. Its never felt half as solid as pedals in any car I've ever been in.

liquidrush Tue Jul 28, 2020 7:50 am

For what it's worth, I don't see anything wrong with using a stock pedal cluster, there's millions of them out there working just fine. Mine had a cheesy pushrod someone stuck in there that pretzled up so I made one from a hardened, threaded eye bolt from McMaster and made a cross pin for the brake pedal end from a drill rod. I'll never bend this one.



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