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New School BMX 2004 - Now => New School Park, Street & Dirt => Topic started by: medved on July 25, 2012, 05:41 PM

Title: 25:9 gearing?
Post by: medved on July 25, 2012, 05:41 PM
Can anyone explain the benefits of 25:9 gearing to me for a trails bike?
I have a dialled race frame that essentially i want to take to the park or trails and have a bit more fin. It currently has 44:16 gearing and wondered what the benefit was if any and whether i should consider changing over?
Title: Re: 25:9 gearing?
Post by: theRuler on July 25, 2012, 05:46 PM
25:9 will feel pretty much the same as 44:16.

To get the 44:16 feel, use the ratio of 2.75:1

Some say that having tiny gearing allows for easier coping clearance when riding into a ramp.
Not sure about that, unless you are literally riding straight in.

Maybe if you are trials riding it helps for getting over barrels.

It does look cleaner though.

And it's not a "new school" thing either.  Rob Ridge rode small gearing in 1990's.  I am sure he wasn't alone.
Title: Re: 25:9 gearing?
Post by: medved on July 25, 2012, 06:23 PM
So aside from the grind/clearance aspect is there any other benefit other than looks?  Am I going to look a numpty turning up on 44:16 basically?
Title: Re: 25:9 gearing?
Post by: Betty on July 25, 2012, 06:55 PM
So aside from the grind/clearance aspect is there any other benefit other than looks?  Am I going to look a numpty turning up on 44:16 basically?

No and no
Title: Re: 25:9 gearing?
Post by: john4130 on July 26, 2012, 09:12 AM
smaller gearing will be a little bit lighter weight with less material used and less chain links.
Title: Re: 25:9 gearing?
Post by: gary67 on July 26, 2012, 09:29 PM
So aside from the grind/clearance aspect is there any other benefit other than looks?  Am I going to look a numpty turning up on 44:16 basically?

Who cares what you look like,fook em :knuppel2:
Title: Re: 25:9 gearing?
Post by: HARORIDER on August 27, 2012, 05:41 PM
So aside from the grind/clearance aspect is there any other benefit other than looks?  Am I going to look a numpty turning up on 44:16 basically?

Who cares what you look like,fook em :knuppel2:

agreed  :daumenhoch:
Title: Re: 25:9 gearing?
Post by: Mdbh on September 19, 2012, 10:51 AM
28/9 is where it's at!!
Title: Re: 25:9 gearing?
Post by: evamedia on September 19, 2012, 11:25 AM
So aside from the grind/clearance aspect is there any other benefit other than looks?  Am I going to look a numpty turning up on 44:16 basically?

I doubt it'll go unnoticed...
Title: Re: 25:9 gearing?
Post by: pickle on September 19, 2012, 12:38 PM
28/9 is where it's at!!

 :daumenhoch:
Title: Re: 25:9 gearing?
Post by: lodge on September 19, 2012, 01:48 PM
44 chain rings bend very easily and was a big problem on freestyle bikes in the late 80's and 90's, the micro chain rings are much more difficult to bend and as a bonus have much better clearance for disasters etc
Some believe you get more power from a big front sprocket (Sean Burns for one), personaly i'm not sure about that one.
Title: Re: 25:9 gearing?
Post by: GavinDavis on September 20, 2012, 09:17 PM
im running on 28/10 which is pretty fruity for quick starts, not as fast top end but still a good set up
Title: Re: 25:9 gearing?
Post by: GaryN on September 20, 2012, 10:30 PM
44 chain rings bend very easily and was a big problem on freestyle bikes in the late 80's and 90's, the micro chain rings are much more difficult to bend and as a bonus have much better clearance for disasters etc
Some believe you get more power from a big front sprocket (Sean Burns for one), personaly i'm not sure about that one.

Perhaps that explains the thinking behind the BSD 44T sprocket that is on my Hoffman D130, it's 10mm thick  :shocked:
Title: Re: 25:9 gearing?
Post by: Mdbh on October 15, 2012, 09:22 PM
im running on 28/10 which is pretty fruity for quick starts, not as fast top end but still a good set up
Wow your a real man! And must have buns of steal! :LolLolLolLol:
Title: Re: 25:9 gearing?
Post by: GavinDavis on October 15, 2012, 10:06 PM
im running on 28/10 which is pretty fruity for quick starts, not as fast top end but still a good set up
Wow your a real man! And must have buns of steal! :LolLolLolLol:

 :LolLolLolLol: Damn right I am....These buns are bullet proof  :LolLolLolLol:
Title: Re: 25:9 gearing?
Post by: darksunday on October 23, 2012, 04:29 PM
25-9 isn't a nice gearing, too stressed,too crunchy...

27-10
30-12 :smitten:
Title: Re: 25:9 gearing?
Post by: dodger on November 14, 2012, 12:09 AM
28-11 here with a bash just in case i bail a grind or fancy a sprocket stall,i remember having a 10mm thick profile blackjack 1 faild feble stall and it was tacod  :2funny: that was £40 gone in all of 2 hours it was never really round anyway tbf
Title: Re: 25:9 gearing?
Post by: gordy on November 14, 2012, 12:07 PM
As others have mentioned, the benefits of a micro gearing set up are . Reduced weight, increased coping clearance and a cleaner look. The down side is that chains can break more frequently, due to the chain having to wrap so tightly around the cassette. A larger gear on the back ensures it doesnt have to "loop around on itself".  This is the main reason why Racers haven't adopted micro gearing in the quest to reduce weight.
Title: Re: 25:9 gearing?
Post by: Mdbh on November 17, 2012, 06:38 PM
Or just buy a good chain my half link shadow cost over £30 but never had a problem! And I've bashed it a few times! :daumenhoch:
Title: Re: 25:9 gearing?
Post by: kev-s on November 17, 2012, 06:52 PM
i run 25-9 and as olly says run a good chain you will have no porbs, i  also run a shadow v2 half link chain for a year now on 25-9 with no probs :daumenhoch: 
Title: Re: 25:9 gearing?
Post by: Nana on November 23, 2012, 08:28 PM
One thing no ones mentioned here ............you go riding park with 44/16 well it would be like going clubbing with flairs and platforms on

All about the street creed  ;D

While your at it wear ill fitting trousers and chain your wallet with a dog leash
Title: Re: 25:9 gearing?
Post by: GavinDavis on November 23, 2012, 10:58 PM
One thing no ones mentioned here ............you go riding park with 44/16 well it would be like going clubbing with flairs and platforms on

All about the street creed  ;D

While your at it wear ill fitting trousers and chain your wallet with a dog leash

 :LolLolLolLol:....Give it a few years and the 44t will come back full circle and will be the best thing in the world to the newbies :) lol.
Title: Re: 25:9 gearing?
Post by: Dingobmxer on November 24, 2012, 07:30 AM
im running on 28/10 which is pretty fruity for quick starts, not as fast top end but still a good set up

same here


Dingo
Title: Re: 25:9 gearing?
Post by: region11 on December 16, 2012, 04:09 PM
I run a 30-12, because the hub i have wont take anything lower.  I do like the gearing. Although, not a lot of choice sprocketwise these days if you run anything over 28t.
Title: Re: 25:9 gearing?
Post by: gib66 on December 20, 2012, 07:45 AM
its all fashion maybe?
25 rings are good for clearance .when i started riding parks i was 44/16 and yes i hit the copings every time lol.i roll in not jump in .anyways i got down to 33 /14 which is tad odd gearing but the 33 cleared most things fine .the one problem with 25/9 is the pressure on the chain and the cassette is masssive compared with larger gearing so they wont last as long/fail faster .
race wise /dirt jump id be around the 33 to 36 teeth for sure look good and neat and not too much pressure on them
Title: Re: 25:9 gearing?
Post by: Jon The Bassist on December 20, 2012, 08:38 AM
I'm going to try some NS 20" this year for the 1st time so I've got a 4130 Supercross XXL frame as a play/occasional race bike. It has a U brake under the seat stays and a 44/16 doesn't look like it will clear the chain. My plan is to try 38/14, hopefully with good chain line and chain tension things won't break when I go for my monster gate starts  :-\
Title: Re: 25:9 gearing?
Post by: gib66 on December 20, 2012, 08:52 AM
it will b okay john its the 25 and 28 micro that i reckon are under serious pressure
Title: Re: 25:9 gearing?
Post by: Jon The Bassist on December 20, 2012, 09:08 AM
it will b okay john its the 25 and 28 micro that i reckon are under serious pressure


Cheers Greg, those 14mm adaptors slotted straight in, there was a couple mm space so they fitted perfectly inside the dropouts with the normal nuts on the outside :daumenhoch:
Title: Re: 25:9 gearing?
Post by: gib66 on December 20, 2012, 09:37 AM
cant beluieve you went bike building at that time night
Title: Re: 25:9 gearing?
Post by: Jon The Bassist on December 20, 2012, 09:57 AM
cant beluieve you went bike building at that time night

I was dead on my feet but giddy about a new bike  >:D , it was a 20 second job to see if they slotted in alright :daumenhoch:
Title: Re: 25:9 gearing?
Post by: Dark Diggler on December 20, 2012, 10:00 AM

it was a 20 second job to see if they slotted in alright :daumenhoch:

thats your age Jon
Title: Re: 25:9 gearing?
Post by: Jon The Bassist on December 20, 2012, 10:17 AM

it was a 20 second job to see if they slotted in alright :daumenhoch:

thats your age Jon

 :2funny:
Title: Re: 25:9 gearing?
Post by: Peter J on December 20, 2012, 12:18 PM
Why do BMX racers still run 44-16 when 25--9 will do the same job  ???

Title: Re: 25:9 gearing?
Post by: Dannywhac on December 20, 2012, 12:30 PM
Couple o'reasons (afaik) Pete - bigger the gear (ie 44T) the less leverage is needed to turn the cranks from the get-go than a smaller sprocket (ie the chains further away from the centre of the cranks) - not to be confused with gear ratios as these can be the same for larger and smaller gears etc. Also, you're less likely to put strain on the chain etc, and easier to tweak gear-ratios etc.
Title: Re: 25:9 gearing?
Post by: SaMAlex on December 20, 2012, 01:07 PM
Why do BMX racers still run 44-16 when 25--9 will do the same job  ???


Just like Danny said, but also: Park/street riders dont often pedal their bikes. Not really hard, proper pushing on the pedals. Where as thats exactly what racers do. Park/street riders have problems with small drivers (9 or 8t) wearing out cos there is so much pression on just a few teeth. Racers would have a nightmare with it. They'd probably have to change their chain & driver every race .... if they even made it through a whole race!  ;D
Title: Re: 25:9 gearing?
Post by: Peter J on December 20, 2012, 03:33 PM
Thank you  :4_17_5:

Very clever lads  ::)

 :daumenhoch:
Title: Re: 25:9 gearing?
Post by: Dingobmxer on December 20, 2012, 09:49 PM
I am putting 36-13 back on my Neal Wood, best of both worlds  8)

Dingo
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