Author Topic: Suzuki GN250 front sprocket  (Read 987 times)

Itsme

  • Full Member
  • ***
  • Posts: 792
Suzuki GN250 front sprocket
« on: July 31, 2021, 08:05:50 AM »
Hi Thumperteers

I am thinking about dropping a tooth from the front sprocket of my GN250 from 15 to 14. Most of my riding is done on back roads where torque is needed and although the GN is fab for a 250 I just wondered if there would be an improvement. I only tend to cruise at 50mph maximum so top speed isn't important. The other day I was climbing a long incline into a fierce headwind and it just felt as though the Suzuki couldn't quite get into it's powerband. Is it worth it do you think or should I just leave well alone and live with the occasional bit of plodding?

Spartacus

Rossco500

  • Full Member
  • ***
  • Posts: 225
Re: Suzuki GN250 front sprocket
« Reply #1 on: July 31, 2021, 10:11:19 PM »
I'd say for the relatively low cost of a front sprocket why not give it a try. I was going to suggest going up one tooth on the rear as a sort of half-way house but they don't seem to be available.

Regards

Tony

SteveC#222

  • Posts: 1900
Re: Suzuki GN250 front sprocket
« Reply #2 on: August 01, 2021, 10:19:02 AM »
I seem to remember I did the same thing when I had my GN and it made it a bit too 'buzzy ( and busy)' for my liking. Also it's suprising how much slack you need to tighten on the chain when you drop just one tooth! :-\
Growing old is inevitable, growing up is optional!

Itsme

  • Full Member
  • ***
  • Posts: 792
Re: Suzuki GN250 front sprocket
« Reply #3 on: August 01, 2021, 10:55:05 AM »
Thank you gents, both good points to consider.

Spartacus

spooky

  • Posts: 1067
  • Sunny Dumfries
Re: Suzuki GN250 front sprocket
« Reply #4 on: August 01, 2021, 02:02:31 PM »
I`m thinking when you got colin i gave you a 14 or 15 tooth sprocket  or maybe both, I think I was running it on 13 when you got it, 14 was pretty good..
Classic efi squadron blue, CG125, Terrot 125, CM200 sprinter,

spooky

  • Posts: 1067
  • Sunny Dumfries
Re: Suzuki GN250 front sprocket
« Reply #5 on: August 01, 2021, 02:04:25 PM »
If you go on  gearingcommander  site you can peruse all the combinations  and change from 41 or 39, i think standard is 41 but i had one with 39/16 combo to try and get it past 90mph..
Classic efi squadron blue, CG125, Terrot 125, CM200 sprinter,

Itsme

  • Full Member
  • ***
  • Posts: 792
Re: Suzuki GN250 front sprocket
« Reply #6 on: August 02, 2021, 08:09:58 AM »
Thanks Rufus. Colin certainly went differently to the Mighty Midget but of course he also had a free-flowing exhaust. I might try a 14 tooth sprocket or I might just leave well alone on the grounds that MM is an old 250 and to be fair goes quite well as it is.

Spartacus

CrazyFrog

  • Full Member
  • ***
  • Posts: 1398
Re: Suzuki GN250 front sprocket
« Reply #7 on: August 03, 2021, 11:57:18 AM »
This may sound counter intuitive, but how about going up a tooth? That would turn 5th into more of an overdrive, but possibly make 4th better suited to hill climbing at 50? I may be talking through my hat though, cos I've never ridden a GN.
2023 Royal Enfield Meteor 350
2021 Honda CB125F

spooky

  • Posts: 1067
  • Sunny Dumfries
Re: Suzuki GN250 front sprocket
« Reply #8 on: August 03, 2021, 06:33:23 PM »
This may sound counter intuitive, but how about going up a tooth? That would turn 5th into more of an overdrive, but possibly make 4th better suited to hill climbing at 50? I may be talking through my hat though, cos I've never ridden a GN.

I did try that and it worked... at one point I had three gn`s all with different gearing, I did get a bit confused, ...and a speeding fine
Classic efi squadron blue, CG125, Terrot 125, CM200 sprinter,

Itsme

  • Full Member
  • ***
  • Posts: 792
Re: Suzuki GN250 front sprocket
« Reply #9 on: August 04, 2021, 01:53:21 PM »
This may sound counter intuitive, but how about going up a tooth? That would turn 5th into more of an overdrive, but possibly make 4th better suited to hill climbing at 50? I may be talking through my hat though, cos I've never ridden a GN.

I understand what you're suggesting Pete, but the problem was getting the motor to 'come on cam', it just wouldn't build the revs to a point where it was in it's powerband. I think in ordinary running adding a tooth would definitely give more relaxed cruising, but I fear in similar circumstances, i.e. strong headwind it might hinder me.

Spartacus

Guzziless Steve

  • Full Member
  • ***
  • Posts: 184
Re: Suzuki GN250 front sprocket
« Reply #10 on: August 04, 2021, 02:25:30 PM »
GN250 and "powerband"?  That must have been missing out of my one  ;D  I found the gearing suited it well to be honest, but mine had been on a fairly serious diet.