DROPPING A TOOTH ON THE FRONT SPROCKET

Lee Frost

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I've just ordered a 15t front sprocket to replace the stock 16t. Reports suggest it'll make pulling away from a standing start without stalling easier (that damned clutch!), and be better suited to offroad riding.
Anyone tried it on the G310GS? Jenny Morgan (for her big ride across the USA on a G310GS) swapped the rear 40t for a 43t and kept the 16t front, but that meant she needed a longer chain. Keeping the stock 40t rear sprocket and dropping a tooth on the front means the same chain can be used and the benefit is very similar...
 
15 front makes it better but not perfect ,still sits at 70 on the road and a bit better on take off . the clutch takes the abuse well so far 8k on the bike so far . the rest of the bike seems ok and no worst than a 1250 for faults ,
 
what size rear tyre do run as this will help with gearing ?
 
think you may have raised the gearing slightly look on tyre radius web page you may need to put a few teeth on the rear sprocket
 
I run 140/80 witch raises the gearing , so head you win tails you lose . I dont feel much effect on the bike other than it turns better , the standard tyre is to fat for the cc of the bike , as for the clutch its never going to get better
 
Many years ago we ran a pre - 65 trials outfit ( 500 Tiger ) the had 12 teeth on the front and 60 on the back.. !
 
so what has that to with a 310 gs ? I have'nt a clue
 
think you may have raised the gearing slightly look on tyre radius web page you may need to put a few teeth on the rear sprocket

This is what Jenny Morgan posted on the advrider.com G310GS forum re gearing...

Based on the stock gearing being 16/40 - that equals a 2.5 ratio...

15/40 = 2.67 = -6.3%

16/43 = 2.69 = -7.0%

15/41 = 2.73 = -8.5%

15/43 = 2.87 = -12.8%

...the percentage change is the drop in speed for the same amount of RPM, or conversely the % increase in torque.

So in summary, changing the front sprocket by -1 tooth offers a little less % change than adding +3 teeth to the rear (as I currently have on my bike), while going to 15/41 offers more of a drop, and is, as I suspected, probably the best combo for more serious off-road use, while retaining reasonable on-road performance too. Any more than that (eg. 15/43) would be too much of a compromise on road I imagine.
 
I've recently acquired a 2018 G310GS and have used it quite a lot over the last few weeks and as of yet not had any issues stalling when pulling away from a standing start nor do I have any complaints about the clutch action

The bike is running stock sprockets 16/40

I'm wondering if these early build bikes were treated to a bit more QA ? (from the VIN it is number 393 off the production line)

 
Hi John, what pannier rails do you have fitted on your G310?
 
Hi John, what pannier rails do you have fitted on your G310?

Hi Lee - they are modified Hepco & Becker so they do not foul the Rally Raid/Scorpion Exhaust

It did originally have RR frames fitted but I personally didn't rate them



 
They look good. I have the RR racks but I don't like the way they slope out as it puts the panniers at an odd angle. Your rack on the exhaust side looks very close to the tailpipe - how will you avoid a soft pannier touching it? I had the same problem with my RR racks until I mounted the tailpipe hanger the 'wrong' way round so it pulled the tailpipe closer to the bike.
 
Lee,
John is being politely circumspect in his description of his recently acquired 310. That's "Bobo" which used to belong to me so it has a few more miles than yours ... and I think it takes those miles for everything to properly settle in and ease that stalling ... or else Bobo just happens to be a good'un from that respect.
If going to kit up the 310 for another adventure, I'd probably go for the Giant Loop U-shaped system again rather than the Magadans.
 
They look good. I have the RR racks but I don't like the way they slope out as it puts the panniers at an odd angle. Your rack on the exhaust side looks very close to the tailpipe - how will you avoid a soft pannier touching it? I had the same problem with my RR racks until I mounted the tailpipe hanger the 'wrong' way round so it pulled the tailpipe closer to the bike.

The end can sits inside the pannier frame and the pannier bag cannot hit it but it is quite close , as a "belt and braces" I would probably fit a Kriega OS plate just to act as a heat shield from the hot exhaust gases

I may look at your idea of reversing the bracket orientation to pull the end can inwards but to be honest I probably won't tour with the bike as I have a F850GSA for that , the racks were more as rear crash protection as my youngest lad who has just passed his test is using the bike ;-)

 
I had H&B racks on mine and had the same concern regarding soft bags. I didn’t modify the framework but did move the bottom rack mounting point to the outside of the exhaust hanger to give a bit more clearance.
I was using Touratech bags with a semi rigid backplate. I fitted some spacers on the mounting points to give a bit more clearance.
No problems with the racks…they survived a few tactical dismounts with no issues.
 


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