Upgrading Kent FS20 Ambush

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10/15/2017 2:10 PM

First things first, I know the bike isn't very good because it is from Walmart, however I do not have the money to buy a new bike or even one on clearance. Please do not tell me to just go get a better one like another forum site did.

I've wanted to get into bmx since I was in school but never had a bike. I was walking around my neighborhood and someone was throwing the bike away because it had a flat tire. I took it home and replaced the inner tube and it rides fine now. My question is, can I do anything to the bike to make it better and more rideable. Like changing the cranksets, sprockets, brakes, or anything else you can recommend.

I would think the crankset or sprocket need to be changed out first due to the pain trying to pedal more than 50ft at higher speeds. But I also have no real ideas of what I am doing when it comes to customizing a bmx bike.


10/16/2017 5:05 AM
Edited Date/Time: 10/16/2017 8:46 AM

The problem you have (& why the "other forum" told you to "just get a new bike") is that nearly any improvements you make to your current bike will ultimately be more expensive than just saving up your money (that you would have gradually spent on new parts for your "Walmart bike") would total more than if you just took that money you gradually saved & bought a used bike or a new Mongoose Legion L100 (around $280). Plus, it's entirely possible that your current' bike's parts wouldn't be compatible with a new frame later when the time comes to upgrade. Lastly, if you have not worked on bikes, you will have a very hard time trying to accomplish what you are trying to do & could end up messing up your new parts and/or your bike, leaving you without anything to ride.

My advice would be to save every penny. Take on odd jobs... cutting lawns, cleaning up yards, washing cars, whatever... to set aside money for a decent starter bike. In the meantime, just try to keep your current ride in decent shape & ride as you can.

I'm sorry if this isn't the answer you were looking for but it's really the most wise decision.


10/16/2017 7:43 AM

No, thank you so much for not just saying throw it away. This is the answer I was looking for as I was thinking I could upgrade this and then possibly save the parts for the new one, or just build one as I bought parts and threw them together. You actually explained why it would not work, and then provided a bike that would fit into my price range. This is the best way to answer I feel.

Would there be any other similar bikes that you could recommend?


10/16/2017 8:43 AM

Don't get me wrong, it may be possible to fit your bike with parts that MAY transfer to a newer frame later. That would be a research thing you'd have to do on your side. BUT, like I said, you;d be getting into money that could be better spent elsewhere (new, more capable bike to build off of).

Now, no offense but with all that said, you really are better off with a new bike. There are tons to be had used that would be WAY more beneficial to your riding. I recently picked up a full chromoly frame/fork/bar bike off Craigslist for under $70. & it is WAY more bike than you have now. You;d be very hard pressed to do better than that just buying the parts for your bike.

Lastly, I'd be very, VERY careful doing any tricks on your current bike. If it isn't there, I guaranty there used to be a sticker on it that said something along the lines of "this bike not designed for trick riding....". So, I wouldn't recommend it.

As for recommendations, in your area I found these as acceptable budget beginner bikes that are worth a look:




10/16/2017 8:54 AM
Edited Date/Time: 10/16/2017 8:54 AM

From what I saw of that bike, the only things you could upgrade would be the handlebars, seat and seatpost, wheelset (but then you'd have to upgrade your sprocket for the proper gearing). Those parts could all be transferred to a new bike later. But a wheelset alone is going to cost about $200 minimum new. Seat and seatpost would cost about $60 (buy why change it.... it's just a seat and post). Handlebars will run about $30 min. new. I believe your stem is the old style stem & wouldn't transfer to a new bike. Brakes aren't of the same type that are on modern bikes.

So, as you can see, if you were to upgrade your wheels and a new front sprocket, that would be about $250. For $250, you could buy a new Mongoose Legion L100 or a good used bike.


10/17/2017 5:49 AM

Yep I agree with Mishinn_Control... buying a new bike would be your best option and the Mongooose Legion L100 I a very good bike actually.... for $250 it has full Cromoly frame bars forks cranks and it has double wall rims, sealed hubs front and rear and a sealed bottom bracket... probably one of the best if not the best bike for your money...


I don't crash, I do random gravity checks...

10/17/2017 6:53 AM

Thought you'd like to see a review of the Mongoose as done by THE local "douchebag":



10/18/2017 5:36 PM

Thank you so much for the help and all of the explanations on why everything would or would not work out. I think I will just save up for either the Mongoose that was linked, or keep checking out craigslist for something cheaper. I hope to ask for your opinions when I am ready to purchase.