Does your frame have a US bottom bracket. If so, I would use this Tioga sealed BB set
Excellent quality, super smooth, maintenance free and all for just £25 from ALANS :o
(http://www.alansbmx.com/images/tioga_3pc_bb.jpg)
!!! CLICK HERE TO VIEW !!! (http://www.alansbmx.com/product_info.php?cPath=116_121&products_id=2065)
Hope this helps ;)
Steve