83 GT Junior

[Jonny]

3/4 way through putting together an 83 GT Junior and have never been crazy about the mini uni seats, so instead went for a 13/16" seat post with a 7/8" top section to take a normal seat. Question is anyone know of a seat clamp for a 13/16" post or just best to shim it out to take a normal clamp?

Jonny

[That Swan Guy]

Shim it or else you could crack your frame.

[MartyC]

WHS ^^^

Shim it otherwise it pinches the tubing and causes a stress fracture.

[Jonny]

Cheers for the info.  They must of made a seat clamp for the GT junior though due to the down tube being a different diameter? 

I haven't seen one myself but going on producing specific parts for mini bikes like stems, grips, cranks etc it surely come with a specially designed seat post clamp?

Jonny

[Andy68]

Johnny, there are 13/16 clamps out there bud but getting difficult to find mate. DK and Cyclcraft are pos your best option. Search USA eBay or put up a please in the wanted section.
I can't find a close up but click on this link to my little bad boy.
http://www.radbmx.co.uk/forum/index.php/topic,172030.msg1728048.html#msg1728048

[That Swan Guy]

Give Andy68 a shout, he's got one in his cave

[Jonny]

Lovely bike that Andy!  Thanks for info on th seat clamp.  I'll wait out and keep an eye out for one.  I'm not doing it to factory spec.  I've put a pair of 81 expert bars on it and the original suntour cranks i've had coated white.  What size chain wheel you got on yours?  I've got a 44 tooth chain wheel but not sure if i should change it looks a bit bit.  Will post a photo.

[Andy68]

No problem Jonny..... To be honest you really want to be 39-41 ish on a junior frameset. What length are your cranks? You fitting 1/8th or 3/8th rims? Your other problem if not sorted is rear brake caliper length. Needs to be  much shorter than ya standard. I'll measure mine later

[Jonny]

Right got you.  It's got some skinny ukai rims, suzue hubs.  I have a dia compe 890 rear brake but not looked at fitting it yet.  I heard the MX 1000 wouldn't grab the tyre so went for that.

[Andy68]

Think that caliper reach will be too long bud, Weinmann 720 on mine with 3/8th rims. If you have 1/8ths then ya gonna need an even shorter reach. I may be able to help you out, offer it all up and let me know 

[Jonny]

Doing it more like an expert with the bars and normal seat.  The difference between the expert and junior is the down tube diameter and BB size, that it anything else on frame length?  I'm not sure on the cranks as they are the originals maybe 165mm?

[Jonny]

Nice 1 Pal.  I actually have the original Weinmann rear brake.

[rodriguez]

Looks the business so far   

A lot of people used weinmann centre pull calipers which are cheap as chips to buy.

http://www.ebay.co.uk/itm/like/301361326620?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=108&chn=ps&device=c&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0

[BMX1973]

Nice ride 

[dannyrobo]

looking good so far jonny 

[CustardLips]

Nice looking build so far. 
Think a blue chainring would look sweet on it.