XR250 gearing

[Ben Breese]

Apologies if its been covered before but I did a quick search and couldn't find anything.

I've got an XR250 that I use mainly for greenlaning and generally offroad, but I do use it onroad too. Currently running 13/47 and it feels like its revving its nuts off at 50mph Whats stock gearing on 250's? I've searched a few other forums and it seems it was different in different countries, but mostly seems to be 13/39 (in Oz and US) or 13/48. Think 13/39 would be too tall for my usage, I was thinking trying 13/42 or 13/45, what do you think?

I've also been told that 3 teeth on the rear sprocket is about the same as 1 on the front, is that right? So 13/45 would be equal to 14/48? My chain and sprockets are ok at the moment so I was thinking of trying a few combinations before buying a new set. I'll probably get a 14t front sprocket and try that with the 47 rear to start.

Also, how many teeth can you drop or go up without having to have a different length chain? Or it is just suck it and see kind of thing?

Cheers, Ben

[phil w]

Hi I think my 250 was as standard which was 13 47 and the main problem was its road speed if you travelled further afield, although 50 was ok on mine. You could drop 3 on rear or go 1 up on front for same thing ratio but a 250 you may lose what grunt it has... Thats why I got the 400
Have you looked on www.thumpertalk.com they cover most on there

[TRANSPORTER]

You can go down as low as a 38 tooth rear sprocket, trust me I have, I,m running 13/39 at the moment only because my local shop couldnt get a 38 tooth rear for me.
I use my 250 for my daily commute round trip of about 30 miles and use it all the time green laning. The only thing that Ive noticed is that sometimes I have to use a lower gear off road than I would of if I was running a 48 tooth rear, but this is only when the hills are steep or the going gets tight.
It also shifts the tourqe a little further down the rev band (or that further up). either way you really wont notice any difference.
Aprt from your top speed or cruising speed, mine now happily sits at 90kph with plenty of throttle left to take her up to around 110kph where it is revving out abit.

[Ben Breese]

I'll probably try a 42 rear then in that case. Where do you guys get your sprockets from? And what do you recommend? Renthal is obviously a well known name, seen stuff from Talon too. Some people I've spoken too say OEM sprockets are the best for wear. I'll probably get a few cheap sprockets just to try the gear ratios (recommendations what/where from?) but when I get a new chain set then I want a good one.

Cheers, Ben

[TRANSPORTER]

Seriously mate dont worry about getting expensive sprockets, Ive had all of the alloy ones and they tend to wear out far to quick, at the moment and for the past couple of years ive been using steel sprockets front and rear, they last for ages and are a third of the price of the all singing all dancing alloy ones.
Also when it comes to chains I gave up using the latest O ring and X ring chains, I took the advice of a local bike shop (Colin Flashman) and got a heavy duty non O ring chain, I lube it up every week and when its needed after rides out in the mud etc and adjust it when required, and that one chain has now lasted me just over a year and Ive still got about 7 more clicks left on my snail adjusters.
Some people may say its false economy to buy cheap but I can tell you Im well pleased that I tried the steel sprockets and heavy duty chain. Give it a go if you dont believe me I think that you will be pleasantly surprised.
As for where to get the sprockets just ask in your local bike shop and specify that you want steel ones and thay should be able to order them up for you.