25:9 gearing?

[Jon The Bassist]

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 

[gib66]

it will b okay john its the 25 and 28 micro that i reckon are under serious pressure

[Jon The Bassist]

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

[gib66]

cant beluieve you went bike building at that time night

[Jon The Bassist]

cant beluieve you went bike building at that time night

I was dead on my feet but giddy about a new bike  , it was a 20 second job to see if they slotted in alright

[Dark Diggler]

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

thats your age Jon

[Jon The Bassist]

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

thats your age Jon

 

[Peter J]

Why do BMX racers still run 44-16 when 25--9 will do the same job 

[Dannywhac]

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.

[SaMAlex]

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! 

[Peter J]

Thank you 

Very clever lads 

 

[Dingobmxer]

I am putting 36-13 back on my Neal Wood, best of both worlds 

Dingo