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

New: Take part in the March Giveaway for HONBIKE Uni4 long-range commuter E-bike valued at $1699 ⚡


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
Specialised Globe Vienna 4 bling bling
Today 08:14 PM
What are your best biking places in your...
Today 06:50 PM
Hi
Today 04:11 PM
Winter Riding
Today 01:43 PM
Moron Wanting an E-Bike UK
Today 08:23 AM
What are your thoughts on E-bikes?
Yesterday 07:22 PM
Is Presta valve lock nut useful?
Yesterday 05:44 AM
The Truth about FAT Tire Ebikes: Sideste...
Yesterday 05:36 AM
Shoes for ingrown toenail
03-17-2023 09:48 PM
Need help identifying Bianchi road bike
03-17-2023 08:58 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. ReapThaWhirlwind
29 posts
no avatar 2. ichitan
28 posts
no avatar 3. enkei
17 posts
no avatar 4. meamoantonio
12 posts
no avatar 5. Talha
11 posts