chain length & sprockets question

[crofty]

I have a DL250 which I'm trying to reduce the revs a bit for touring. The current set up for sprockets is 14x47 which is standard. I have ordered a 15t front sprocket and a 46T rear, I am making the assumption that reducing the rear by one cancels out the front increase and planning to buy a standard chain which is 116 links.   

[Gert]

Have a look on https://www.gearingcommander.com to see whether there is data wrt your ride. If not enter the current data for your ride and then enter the proposed sprocket size under custom. Their calculator should be able to provide you with expected rpm vs speed info, which may help provide answers to your proposed setup. While these figures are theoretical, I have found the results reasonably accurate, pending on the road surface / gradient, wind and other weather conditions.

[Mojoman]

Hi crafty, did your gearing change make much difference, did the 116 length chain fit OK and where did you order the items from please?
I have recently purchased a DL250 2020 reg and finding it difficult to find alternatives to standard gearing online.
If you still have bike or not any other mods did you try ?
Many thanks
Mojoman.

[baz-r]

I have a DL250 which I'm trying to reduce the revs a bit for touring. The current set up for sprockets is 14x47 which is standard. I have ordered a 15t front sprocket and a 46T rear, I am making the assumption that reducing the rear by one cancels out the front increase and planning to buy a standard chain which is 116 links.   

I have a DL250 which I'm trying to reduce the revs a bit for touring. The current set up for sprockets is 14x47 which is standard. I have ordered a 15t front sprocket and a 46T rear, I am making the assumption that reducing the rear by one cancels out the front increase and planning to buy a standard chain which is 116 links.   
[/quote]

what sprocket did you use at the front because there is no identical sprocket for that engine? there are "520" pitch sprockets with a identical spline hole but all are different thickness or offset at the mounting point to the original.
as far as I know only 14t is the only fitment for the gw/gsxr/DL250 engine. just got a 45t rear and that will take the std 520 116 link chain I'm trying this first as 14/41 will need a 114 links
14/37= 3.36:1 (orignal DL250 gsx250r 18-22)
14/36= 3.29:1 or 2.1% lower (gsx250r 2017/gw250)
14/35= 3.21:1 or 4.3% lower - 116 link chain "OK" (jap sv400)
14/41= 2.93:1 or 12.8% lower (big step up but not far off the 15/46 setup) 116 link too long (jap gs400)
14/39= 2.79:1 or 15.2% lower (gs500)

15/46= 3.07:1 or 8% lower

as a rule of thumb you take the chain length for the factory setup and add or subtract the tooth count added or lost then half it to get what chain you need as the chain is only in contact only around 50% of each sprocket. remember you can only go in evens on chain size too!