Reverse kit troubleshooting
 

I need some input about installing.when I slide the unit on new shaft the right side of the unit stops at what looks like The correct spot,now the left side floats and has 1/2 or more gap before lining up sprocket.the reverse In The picture gap is only about 1/8.should I shim out my Sprocket?I have not started engine yet because I don't want to damage assembly.Any help will be appreciated.
Tim
yerfdog Spiderbox

Did the kit come with shims? Either way, You need to shim out the entire reverse box to the axle sprocket. Some ppl have used washers. But best to find correct size shim. If need to get a longer one then need, then cut down. But if only 1/8. might get away with a few washers. Maybe a temp fix, until you get a good shim for it. Shim, or what ever you use, needs to fit good on shaft, but thickness needs to slide in on the left side of box, so doesn't rub the outside of it. Should fit inside that gap, or inside those nuts on the left.
When you get to the right line up, put it together. On chain. tighten up the box to the shaft. And give it a short ride. or just go up and back with it for little bit. See if it still lines up. In both cases, where it first lined up, I had to change slightly after testing it out.
But that may be not in this case. Just would double check the alignment after giving it few test runs.

Here are a few pictures of problem I'm having.

Reverse
 

I finally got some shims to finish installation.Now I need to move my sprocket over to the right,but engine has threaded mount in the way.Will it hurt to grind ear off of the engine case?
Thanks Tim
I tried to attach picture not sure if it worked

If your talking about bottom of case? Shouldn't hurt. Take it you got bigger axle sprocket? Its normal for it to need some grinding. I dont take it all the way off. Just enough to have some clearence.

Thank you for the quick response.Yes I did place a 39 tooth sprocket and an upgraded axle.BD just emailed me and he is sending me parts to get my reverse moved more to the left.
Thanks again for quick response not ever sure about cutting on cast case
Tim

Wow that's not what I was expecting.Finally got battery mounted today,got to drive it down to the end of street and on the way back "pop" reverse assembly broke.I emailed Travis at BD but it was later in the afternoon.I hope some of you can give me some input on what caused this .had grease,spacing was correct,spindle nut was tight,shifted fine in back yard several times,and the weird part is I was going forward at full speed when this happened. here are some pictures. (Should I use this puller to try out to get Sun gear off)

Here are some better pictures of reverse box.It's funny I have been building dirt track,drag cars since I was 16. Worked in industrial maintenance for 16 years before had to stop due to health reasons and now this stinking gy6 reverse box has kicked my butt:banghead:

I would give Travis a call, the kit should of had everything needed for a proper fit.

Hey Tom
I have been emailing him back and forth and he has been very helpful.I am just at the point where I need fresh eyes on this.it's been several attempts and everything was correctly lined up,nut tight but not over tighten,The only thing I was not comfortable with before test driving was not enough threads for shaft nut but I had it secured and locked in.I had 1 spacer with step and two thin flat washers.I had to grind down motor mount bolt head so chain would not hit,but it was clear.cable was secure with plenty of slack for shock travel.This is the only problem I've ever had with BD parts and I got more money in suspension upgrades than I paid for buggy.:drive:
I know he will stand behind defective parts. i just want to get as much input about this i can.I just wanted outside input just in case I missed something.
"to much knowledge is like to much money I would be fine with either"
Tim

curious as to what the outer fixed half of the reverse box looks like. I take it (going by pics) you had the brace hooked to something either engine or frame. for the box to come apart and take out the brace mounts really sounds like something caused the two case halves to engage together at the worst possible time.

This was the only damage done to outer case.I had it bolted to engine with assembly bracket.I cut the inner bearing collar off a minute ago and the sun gear drive came off and will slide over spline of another shaft ,it looks like the inner bearing collar of shaft needle bearing #14 in drawing.but it looks like there were two welded to shaft in picture because sprocket side of the unit never moved after I took mounted side off

I agree, in forward the internal planetary gears and sun gear are locked together in unison, and there isn't an opportunity for gears to catch on each other. I believe whatever happened caused the planetary set to shift over and try to engage reverse while the kart was moving forward.

My bet is the cable arrangement, movement of the swing arm pulling on the cable. Don't worry about warranty, I'm sending out a replacement sun gear and collar. The planetary and outer ring gear look fine so this should take care of it.

Although I've never seen a sheared sun gear before, usually when reverse gets inadvertently shifted while moving the planetary gearset grenades into a bunch of pieces and chews up the outer ring. Interesting, the higher speed may have saved the rest of the gearbox.

I'm wondering what the deal is with the seized collar. You're saying that it seems to have welded itself to the output shaft? That would have been friction related, most likely not related to the other issue. I could be wrong, but it sounds like there were two underlying problems.

Let me know when you receive the replacement items, I'd like to see a few quick pictures of the final assembly and cable routing just to make sure.

that was the other thing i was wondering too, but it doesn't take much of a piece of debris to weld and lock up a shaft. Had it happen to the kawi 750D engine on my scag when the governor let loose. 1 weight pin got between the crank and aluminum block case bore hole next to the plain bearing and seized it solid.

Take a look at your shaft and the inside of the collar, one or the other or both might have witness marks and embedded foreign metal

Trust me I am going to ask my wife to video (her hands don't shake :laugh2:) every step and part of the next install.I really want to know why this happened.because if I did something wrong i can accept and learn from that and will help with the cost.Travis i am thankful for all your help and covering these parts.I think it was the inner collar of the needle bearing that was stuck but I can't tell what is was after I cut it off. I

If anyone has pictures of this type of reverse box taken apart , so I can see how everything is laid out. please post them

Travis got my parts to me fast and now I have to figure out how this thing goes back together.Don't worry I will not assemble anything until I get back with him to make sure what is correct.I just thought I would post some pictures because there is very little detailed information out there on the inside of these kits.

I would check with him but any of the rev units I have worked on have a spacer between engine and rev unit.

Yes sir Tom I do have 2 step down 12mm spacers and a couple flat washers.These bushing are all internal.I think it goes between needle bearing bushing and triangle gear connected to the right side housing but not

If I only had a cliff
 

We got 4 to 5 inches of good snow so I got spiderbox out put it in reverse back up put it in forward stays i reverse.tapped with screwdriver and rolled gocart forward went out of reverse and nothing.l tapped and rock tap and rock cable was loose but yolk would not engage to forward.Sad thing is I finally got angry enough i cut the cable so I could tap yolk in to get it back to shop tap tap nothing .could pull it out but would not go into forward.walk off and left in snow.This is why it i had a cliff I would push it off.Only good thing about it my 8 year old stood there holding the light and never raise a fuss about it not running kinda made me proud he is more mature than his dad����

Update
 

Finally tore every piece of this reverse gearbox apart and washed and inspected every part.the only thing I found that could cause SHIFTER YOKE to bind is the flat part of the fork has a little play in it looks like weld has broken where it is connected to the shaft.I am thinking I'm probably going to reweld it myself instead of trying to find new one.I have always been nervous about tearing this thing apart because I was unsure how it work and $239 is a lot of money to me.The only yokes I found online seem to be more heavy duty than the one in my gearbox so not sure if they are direct replacement.


I put up pictures of my yolk .look at the angle

Finally had the opportunity to put my new reverse box on cart.had if up and running in 30 minutes.now I will be getting the other one repaired and I will have spare.