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-1 tooth, front sprocket

14K views 41 replies 12 participants last post by  fork12 
#1 ·
So this bike (2018 790Duke) is 99% used for communting to work, in heavy traffic, with a part through a suburbon area with lots of roundabouts (Circles for our South Afrikan readers).

I'm finding it tricky to negotiate very tight turns (typically 90degree) whilst also cancelling the signal and resignalling whilst also feathering the clutch.

I can try not singalling (not good as oncoming traffic thinks i'm going straight)
I can try just going faster (i'm not super comfortable here, we're talking large potholes, school children, wet manhole covers)

what i've been doing is having the throttle all the way off and coasting round with the clutch out. This works most of the time but is difficult to do smoothly espeically when you are braking into the junction

I thought a rear sprocket with more teeth would be a good idea?
It will reduce my top speed (not really an issue as i'm 99% in the city) but i'm hoping it will raise the revs a bit so slow manuervers are easier.

Has anyone had the same issue?
has anyone installed a larger rear sprocket? what was the effect?
 
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#17 ·
I'm thinking of going the 15T front sprocket route. 6th gear seems too tall - I can barely get into 6th on most of the roads I ride here in the Lower Mainland, and it sounds like going one tooth less on the front is a bonus for commuting too. Where did you buy your 15T sprocket? Are they available from KTM dealers?
 
#12 ·
so i got the bike back from the dealer. it does seem much smoother to start and happier at low speeds but i'm not sure if it's just in my head. There is one particualr roundabout where i can almost go round it in first without pulling the clutch in and today was no change. So not really sure if it was worth it.
will give it a few more days.

Also got a new dashpod under warranty, it's so clean!
 
#13 ·
ok, had another day or so, yes i think it makes a difference. it's not comfortable on that roundabout, but it is manageable. It seems silly to redesign the drivetrain of a bike for one roundabout but i use this to get to work everyday, and the roundabout is just by my house so literally every journey will include it. it's not a huge difference though. if the bike is 'almost' right then this will help but if you are finding the gearing way out for your style of riding this isn't the panacea (imho).
 
#27 ·
Ohhhhhhh yeah sorry it was late when I was on here!!! Yes, that would make for quite a jacked up ride indeed! Haha! 15 tooth front, 42 rear is what I meant!
Yeah, I'm excited to see the difference.......taking possession of the new 890 R this week so once I get through the break-in I'll see how I like the 16/41 gearing first. Might as well have the options on hand if I decide to tweak things a little. Going to be commuting 100 miles a day on wicked, kick-ass twistie Sierra Mountain roads so it'll be cool to check out all the options!
Thanks for the clarification!
 
#28 ·
Ride it for a while and see if you really need to change it. All depends on what roads you are on and the speed you ride. I honestly find myself wishing for a taller 6th gear on the highway and going lower would make that worse. First gear is already pretty low and if you grab a handful of throttle, the front in coming up in a hurry so make sure you leave the rider aids on as you learn. It is stronger than a lot of liter bikes down low and it is very lightweight. Once you get it broken in, you'll see what I mean. It is a lot of fun.
 
#36 ·
Just as a point of reference. I run a -1 front.

Yesterday I was out and minded myself to a small test. Gear vs OEM speedo.
A usable non sporting rpm/gear test. Good roads but with traffic. And a fair sprinkling of Police and Cameras. So more or less legal.

imo 6th is too tall for 100kph even with a -1. I'd say 110-115kph is a reasonable 6th gear trundle speed beginning.
130kph is barely above half revs. And 160kph happens fast with no gear change.
Much below 85-90kph and I change to 4th.
 
#37 ·
Given the wide, substantial, and very flat torque curve, I'd say you have a lot of choice in gears. So if you are limited to such low speeds, seems like stock gearing isn't going to be a huge hindrance. This motor isn't wan you have to rev out to make serious power or torque. If you are really wanting to match gearing to road speed and after effectively limited to 130km/h, why not go -2T up front and maybe up 2 or 3 on the rear. Who needs first gear anyway? ;-)
 
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