Destroyed Crankset, Lesson Learned.

[6zfshdb]

When putting my bike on a vehicle rack , I usually remove the seat post. This eliminates some weight, keeps the seat dry during inclement weather and prevents theft during transport. In the past, I would stuff a rag in the top of the down tube to prevent debris from entering. I learned the hard way this isn't the best idea.

After doing this for several years, the crank on my Trek MTB became stiff and started making a grinding noise. When I dismantled the crankset, I discovered the bearing case was fouled with water and fine debris. Apparently it had worked its way past the rag, traveled down the down tube and into the bearing case. For some reason, there is an opening between the down tube and the bearing case on the Trek which can allow contaminants to enter???




I'm not sure if this is the case on other bikes but I'm taking no chances with my new e-bike. I started using a plastic cap over the down tube opening.




I also use a similar cap on the seatpost end. It keeps the shim and QR clamp on the post and protects the post end & other gear from damage during transport.

 

[steve mercier]

How long have you had that bike?

 

[6zfshdb]

The Trek I've had for 15 years. The Pedego Intecreptor in the pics above I got this past March.

 

[batmick1]

Even like that you will have some water seepage into the bottom bracket area. Most frames have little vent holes at various locations from the welding process and even around waterbottle screws or along the headset some water will eventually enter and make it to the lowest point of your frame.
15 years is a pretty good lifespan for a bottom bracket and a replacement is cheap ($15-20) and easy, if you have the right tool. Just make sure you get the correct axle length and type. You should not have to replace the entire crankset.
I open and clean out the bottom bracket shell about once a year or so to clear out any crap that has accumulated there.

 

[steve mercier]

Anyway I guess that means I should stop riding through these huh?

 

[batmick1]

Anyway I guess that means I should stop riding through these huh?View attachment 28213

You can still ride through there, you just need to deal with the consequences...

Like you can eat any mushroom, but some just once.

 

[indianajo]

Having lost an automatic transmission case to high water that never drained out and corroded a cylinder, I drill holes in the bottom of my bicycle crank area. I do ride through floods worse than that, up to 15" deep. I also use the hole to turn the bike upside down and pump oil in there to lubricate the crank balls. Stopped a crank squeak once.
I deleted the quick release on my seat post and installed a cam substitute a stainless allen bolt and elastic stop nut. Has prevented theft so far, in lots of very public parking places. Front wheel quick release removed also, bolts and nuts prevent casual vandalism.

 

[steve mercier]

It was easily 20 " in the middle. I might have tried it on my cheapo bike.

 

[mrgold35]

Do you have a link for the caps you used? I have Bodyfloats on both ebikes and I take them off when I travel on the bike rack. I usually stuff a rag or shop towel in the seatpost hole assuming it was better than nothing.

 

[6zfshdb]

Do you have a link for the caps you used? I have Bodyfloats on both ebikes and I take them off when I travel on the bike rack. I usually stuff a rag or shop towel in the seatpost hole assuming it was better than nothing.

I buy them from Mocap : https://www.mocap.com/plastic-caps-round-vinyl.html

You'll have to measure your down tube diameter to get the right size. The caps stretch a bit so you don't have to be exact.

 

[Drew]

I have Bodyfloats on both ebikes and I take them off when I travel on the bike rack.

I guess you are doing that for security? I have a Bodyfloat and I put an ABUS Nutfix on the seatpost, no more security worries!

https://tinyurl.com/ybxc4nfx

 

[6zfshdb]

Yes, I remove my Thudbuster with SpiderFlex seat to prevent the theft of $300 worth of equipment. Using a nutfix would certainly work but I use a QR clamp since I'm constantly making seat height adjustments.