Axle Keys???

[bellinoracing]

How does everbody keep their axle keys in the axle? The parts I used to use you had to tap the key in the axle with a hammer. but these aluminum sprocket hubs I started buying fit the key so lose that they fall out. Would a couple drops of threadlock keep it from falling out?

thanks

[Mike Bean]

Sounds kind of weird. What kind of axles are you using steel or alum?

You could always get some locking collars and put them on the axle on each side of the bug to keep the keys in.

Is your key stock and the key way in your axle a true 1/4"? Did someone cut the key way for you?

Mike

[bellinoracing]

Yeah the axle I am using is a solid steel axle with a silver coating. The keys fit a little loose in all four hubs so could it be the keys? For keys I just bought a piece of key stock that I cut into the 4 lenghts that I needed. Do the pre-cut keys fit better? Any body else run into this problem?

thanks

[Mike Bean]

I would measure the key stock with a dial caliper and see how close it is to 1/4".

Did you have someone make you the axle? Or did you buy one already done from a place?

Did you say the key stock is also a little loose in the hubs them selves?

Mike

[bellinoracing]

Yeah I bought the axle already made from Mfg supply. Yeah the key stock is loose in both the axle and the hubs, so I am guessing it is a problem with the key stock. Any idea what it should measure, exactly 1/4" or a little over? this has happened to me with several different pieces of key stock so maybe I should try getting some from somewhere else, maybe a kart shop and see how it fits.

Any more suggestions? would be apperciated

thanks

[CHEVMALI454]

i have the same problem with the keystock, they re bit loose,they re looser on the axle side but for the hubs they fit tight so i buy the keystock from other places and still doing it so i tack weld keystock to the axle and it works fine , maybe you can try that? i dont know if it is a bad idea to tack weld the keystock to the axle?..

[elvergon]

I´ve seen guys in racing karts that use the typical plastic belts that are used to hold cables together. I don´t know the english correct name for them, but you can find them from the home depot to a electric shop.

Keys are made so they won´t have any space between the key and the hub, but it may however move along the axle.

You can also tack weld it but if the key gets to break, or not being correctly positioned that´s probably the end of the axle.

People of the Society of Automotive Engineers Mini baja competition used to tack weld the keys on the axle for the 4 hours endurance race. Most oppresors would fall out in the first 2 hours of the hard race. However they tested it a lot of times before tack welding it, so make sure you have everything set up straight

[stool-sample]

If you want it to look nice, use split collars like Mike stated, or wrap it a few times with electrical tape. It normally holds for me when Im racing. I like to have my sprocket hub freefloat about 1/4"

[Mike Bean]

Yeah I bought the axle already made from Mfg supply. Yeah the key stock is loose in both the axle and the hubs, so I am guessing it is a problem with the key stock. Any idea what it should measure, exactly 1/4" or a little over? this has happened to me with several different pieces of key stock so maybe I should try getting some from somewhere else, maybe a kart shop and see how it fits.

Any more suggestions? would be apperciated

thanks

From what you are saying about the key stock loose in both the axle and hubs makes me believe the key stock is not true. My key stock fits real nice in my hubs and decent in the axle. I usually do not have problems with the key stock coming out unless a set screw loosens up.

Get some new keystock... Take your old with and match it up to see if it is a bit larger.

Mike

[voodoo_stepchild]

I had the same problems with a steel axle I bought from northern. I since have ended up scrapping that axle since I run 1 1/4" axles now but I made my own keys and had to mod the axles pretty hard. When I mic'ed the axle it was .268 wide and .140 deep, 1/4" is .250 wide and .125 deep on the axle. I ended up using a 5/16 keystock and I chucked it up in my mill and used a fly cutter to cut it to my specs for that axle. But as I mentioned earlier I have since scrapped that axle setup and I am running 1-1/4" on all my bsr's now. Also I noticed that the keystock that you purchase from home depot or lowes or somewhere comparable is not the correct size. I have measured from .010 to .030 difference in sizes. Crazy I tell you

Voodoo

[cerobb]

I experienced the same problem. Loose keyway such that on our first run the keys fell out and both my disc brake and sprocket began to move on the axle until the sprocket became out of align with the drive and the chain broke. I purchase both the steel axle and key stock from Barstool Racer Supply so one would think they would be of the same tolerance. To fix the problem, I placed the sprocket and brake back in place and then put tension on the key / keyway as I tightened the set screws. Then I used zip ties on either side of the sprocket and disk brake. Second test run worked great. It still looks like the keys loosened a little but the zip ties kept them from sliding out of place. If anyone else has ideas other then welding them in place, they would be greatly appreciated.

[CritterBuddy]

Had the same problem with the keys on my Shrine parade vehicle. Because the axle is pretty well hidden by the body, I cut the keys 3/4" longer than they needed to be so they stuck out and put a good stainless steel hose clamp on it.

[Snakester]

A few dots of super glue does the trick...or silicone...:thumb:

[Mike Bean]

On my last build with the 125cc I put tie wraps on each side. I cut the keys so they fit inside and a nice little tie wrap on each side will keep it from walking.

Now if you are using a steel axle, I find that using the steel lock collars as a replacement for the tire wraps on the sprocket hub and brake disc work the best. I find that those set screws can keep coming lose from all the vibration the BSR's have.

I once lost the set screws on my brake disc, so I just left the lock collars in place and never had another problem.

Mike Bean