Have questions or want to discuss cycling? Join Now or Sign In to participate in the BikeRide community.


Trek 4300 bottom bracket
#1
Anyone know the make/size bottom bracket for a 2005 trek 4300 bike.
It has the stock crank set SR, 24/34/42 teeth.
The BB SHELL measures 73mm and is square tapered fit.

Thanks..
  Reply
#2
if you have it, just measure it. A Shimano UN54/55 is a good replacement for not a lot of money.
Nigel
  Reply
#3
The 73 mm is correct. To add to Nigels advice, make sure you get a BB with English Thread and not Italian. The UN54 can be had in both.
73 is your shell width. The next important number is your axle (spindle) length. It might say '73-113' in the description. You'll have to pull the crankarms to measure this. If the crankset were Shimano, we could easily find what length was required. As it's SR, a bit more difficult.
If I were a betting man, I'd bet on 73-122. SunRace stuff seems to run wide. What diameter is your seat tube? What front drlr?
Wheelies don't pop themselves. (from a QBP fortune cookie)
  Reply
#4
Impossible to have a Italian thread on a Trek, it should be English...
  Reply
#5
(04-02-2012, 08:44 PM)bobtravers Wrote:  Impossible to have a Italian thread on a Trek, it should be English...
But, but, but Bob! It's not impossible to have an unknowing LBS rat just pull a BB off of the shelf and sell you the wrong item and then want to charge you to clean up the thread damage that YOU did by attempting to install the wrong BB. Never happens in my shop but, I've heard stories. Just looking out for rocky. Dig?
Wheelies don't pop themselves. (from a QBP fortune cookie)
  Reply
#6
Euh, that's why people are asking question on this forum when they do not know the answers... Officially, a Italian thread BB wouldn't fit installing it with your hands...

Your answer is almost the same as: is it possible to run a car motor with sand instead of oil inside, cause the mechanic didn't look at the right bottle to put in???
  Reply


Possibly Related Threads...

Forum Jump:

[-]
10 Latest Posts
Thoughts on tariff effects on the cyclin...
Yesterday 11:06 AM
braking by reversing the pedals
Yesterday 10:15 AM
Post-Ride Nutrition
04-03-2025 02:06 AM
🚴‍♂️ Saddle Up for the Belgian Waffle Ri...
04-03-2025 02:03 AM
Pre Ride Food Intake
04-03-2025 12:14 AM
SAVA Explorer 6061?
04-02-2025 03:31 PM
Zwift v Spin v Wahoo
04-01-2025 05:59 PM
Have you Ever Tried an Electric Bike?
04-01-2025 05:07 PM
Good Morning from SW Ohio
04-01-2025 07:32 AM
(So California) PV Dr to be closed to bi...
03-31-2025 09:14 PM

[-]
Join BikeRide on Strava
Feel free to join if you are on Strava: www.strava.com/clubs/bikeridecom

[-]
Top 5 Posters This Month
no avatar 1. GirishH
22 posts
no avatar 2. Flowrider
18 posts
no avatar 3. Jake1
12 posts
no avatar 4. meamoantonio
12 posts
no avatar 5. SPINMAN
8 posts