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I recently change the rear sprocket to 1 tooth larger. For me , it didn't change the low end enough. Has anyone changed to 2 teeth larger on the rear? How is is? Im not looking for top end over 120mph Thank you
 

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Yes, I and many others went with the 40 tooth rear. It's quite a bit better - one tooth is not enough. You could go more, but likely need a longer chain, which I didn't want to do. I'm happy at 40T.
 
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I recently change the rear sprocket to 1 tooth larger. For me , it didn't change the low end enough. Has anyone changed to 2 teeth larger on the rear? How is is? Im not looking for top end over 120mph Thank you
I am one of the "many others" @Thumper1500 has mentioned, and I have played a bit to find the sweet spot that works for me and our riding here in Oz. I initially went to a 16t front - down from stock 17, with a stock 38t rear, and that was a big improvement, increasing engine rpm to where 6th gear was usable down to about 100km/h, which is the highway speed limit here. I replaced the chain at 30,000km and went back to the 17t front and 40t rear, mostly because of availability at that point in time. By the seat of the pants it feels the same gearing. I was able to use standard length chain for both of these.

The big question you should ask is "What am I trying to achieve by changing gearing?" If +1 on the rear hasn't done much .. and it wont, maybe leave the 39 on the rear and go to a 16 on the front. That would be doable with standard length chain, and importantly bring 6th gear to usable right down to 85 or 90km/h .. if that is what you are chasing.
 

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Do the 1290 R and the SDGT come with different stock sprockets? I'm having a hard time imagining my R with an even shorter first gear (the first three gears really). As it is I can short shift first and give it 1/2 throttle in second and the wheel comes up. Hell, on several occasions I have left a stop sign and realized the bike was in 3rd gear :grin2:
 

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While I find it hard to think of a 1290 needing more low end, I personally have always gone down on the countershaft sprocket rather then up on the rear. I would highly recommend getting a 16T front sprocket. This has tow advances for you. You can mount the 16 t front and leave the 40 t onthe rear at first. If that is “too low”, then leave the 16 on the front and go back to the 39 on the back. Sorta like two gear choices for the price of one. In case you haven’t figured it out yet, changing one tooth on the front is like changing 2 1/2 teeth on the back. So leaving the 40 on the back and putting the 16 on the front is almost the same as leaving the 17 on the front and going to a 43 on the back.

Hope that isn’t as confusing as it was to write
Craig
 

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Discussion Starter #7
Ill get a 16 T and see how it goes..Where did you get the 16T or anyone else can chime in?..... Thanks all! BTW.. I live and ride in Medellin Colombia.. The elevation here is 5000 to 7000Ft and there are only 2 GTs in the country. Not alot of straight roads, hence more torque wanted. About 20 1290 Adv's in the country though
 

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Cheers all,

I have also used 17/40 and 16/38 and currently run 16/40 sprockets on my 17GT.

The SDR is a different bike - if it runs the same sprockets as an SDGT and has low gearing, then it has different internal gearbox ratio's to the SDGT.

The basic info is 17/40..... 15 min swap, same chain - gives 250rpms increase in 5th at 100kph.

16/38 - gives 500rpms in 5th at 100kph but feels pretty much like the 17/40 and requires more effort than the rear to swap.

16/40 - gives 750rpms in 5th at 100kph, but makes city riding very very nice and brings 6th into play at 4k rpms for 100kph (no chugging)........ 6th is a PITA as it has a 700rpm gap to 5th, so it is an awkward overdrive instead of a nice close ratio gear..... however I am finding that I now use it more with the 16/40 set..... BUT it does require some faster gear swapping than with a 17T.

With a 16t, I though I lost some of the torque I liked with the 17, however I will try the 16/38 again to make sure - certainly a 16/39 would be well worth a try since you already have that sprocket.... that will lower 1st so traffic will be easier to handle - I think it brings 1st down to 19kph vs 23kph for the 17T before chugging forces a clutch pull.

I recommend the 17/40 as the best value/quickest way to make the GT nicer as a 5speed - I was happy with that but just wanted to try a 16t for myself....... if you are buying a new chain, then maybe you could try a longer chain with 17/42 sprockets....... :|...... thats what I think I'll be doing at 40k kms when my chain & sprockets are up for replacement.

:smile2:
 

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Ill get a 16 T and see how it goes..Where did you get the 16T or anyone else can chime in?..... Thanks all! BTW.. I live and ride in Medellin Colombia.. The elevation here is 5000 to 7000Ft and there are only 2 GTs in the country. Not alot of straight roads, hence more torque wanted. About 20 1290 Adv's in the country though

Yeah, I bought the KTM genuine one as it has the dampening material...... and the local parts guys said the tech's had had issues with non genuine fronts...... didn't say what they were.... but the price wasn't much different so I went with the KTM 16T.

:wink2:
 

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The SDR is a different bike - if it runs the same sprockets as an SDGT and has low gearing, then it has different internal gearbox ratio's to the SDGT.
This has been some very difficult information to obtain for some reason. But from what I can dig up they both run a stock 17/38 sprocket set up and share identical transmissions.
https://motoperf.com/motorcycles/KTM-1290-Super-Duke-R-2014-926667

I'm having a hard time understanding the obsession on this board with having the bike in 6th at 62 mph. It's meant to fly...if it doesn't need 6th ride it in 5th!
 

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This has been some very difficult information to obtain for some reason. But from what I can dig up they both run a stock 17/38 sprocket set up and share identical transmissions.
https://motoperf.com/motorcycles/KTM-1290-Super-Duke-R-2014-926667

I'm having a hard time understanding the obsession on this board with having the bike in 6th at 62 mph. It's meant to fly...if it doesn't need 6th ride it in 5th!
Thanks for the links @Nubicon Appreciate the search.

The 100km/h (62mph) "obsession" comes mostly from the Aussie side of the forum, where it is our enthusiastically enforced national speed limit. We are simply trying to have the bike run smoothly within those limits. I certainly would love to ride the bike as it was engineered and geared, but unfortunately I wouldn't be able to do it for very long. The fines alone would be almost enough to purchase a new SDGT. So we gear it down to ride in top gear at or just enough over the speed limit to be within tolerances, and have the engine operating in the sweet spot above 4000rpm, though this consideration has faded a bit with the latest ECU reflash. :wink2:
 
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I'm having a hard time understanding the obsession on this board with having the bike in 6th at 62 mph. It's meant to fly...if it doesn't need 6th ride it in 5th!
G'day Nubi,

No obsession with riding in 6th at 100kph here........ I quote revs at 100kph as a reference so the reader can compare/decide if that is the effect they want for their local riding conditions....... :wink2:.

Sometimes it's the only way to communicate effectively across languages/borders (world wide web and all eh :wink2:) ..... might be tedious but quite a number of readers have expressed appreciation for the data so they can make an informed decision.

:beer:

PS re; @AusPete comments.....I've managed to hold onto my licence for 45yrs and still have fun.... just gotta be clever about it....... but while we have large open spaces, we also have wildlife that can jump in front of us, droughts that force animals to feed on the grass on the side of our 'D' grade back roads etc etc...... in Aus, it's ride to survive more so than look out for a speeding fine......... :wink2: (and if we stuff up, it's often a long wait for an ambulance/helicopter rescue...... painful...... oh, did I mention the square headed car (& truck??:surprise: ) drivers we seem to have in abundance in these 'modern' times...... :frown2: ).

Gotta laugh eh?......
 
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Regarding 1290 GT sprocket change

Cheers all,

I have also used 17/40 and 16/38 and currently run 16/40 sprockets on my 17GT.

The SDR is a different bike - if it runs the same sprockets as an SDGT and has low gearing, then it has different internal gearbox ratio's to the SDGT.

The basic info is 17/40..... 15 min swap, same chain - gives 250rpms increase in 5th at 100kph.

16/38 - gives 500rpms in 5th at 100kph but feels pretty much like the 17/40 and requires more effort than the rear to swap.

16/40 - gives 750rpms in 5th at 100kph, but makes city riding very very nice and brings 6th into play at 4k rpms for 100kph (no chugging)........ 6th is a PITA as it has a 700rpm gap to 5th, so it is an awkward overdrive instead of a nice close ratio gear..... however I am finding that I now use it more with the 16/40 set..... BUT it does require some faster gear swapping than with a 17T.

With a 16t, I though I lost some of the torque I liked with the 17, however I will try the 16/38 again to make sure - certainly a 16/39 would be well worth a try since you already have that sprocket.... that will lower 1st so traffic will be easier to handle - I think it brings 1st down to 19kph vs 23kph for the 17T before chugging forces a clutch pull.

I recommend the 17/40 as the best value/quickest way to make the GT nicer as a 5speed - I was happy with that but just wanted to try a 16t for myself....... if you are buying a new chain, then maybe you could try a longer chain with 17/42 sprockets....... :|...... thats what I think I'll be doing at 40k kms when my chain & sprockets are up for replacement.

:smile2:
Any
one know if there is a way to readjust the speedometer once you make the sprocket changes?
 

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Any
one know if there is a way to readjust the speedometer once you make the sprocket changes?
No need to @Speedy14 The speed reading is taken from the ABS rings on the front wheel, so doesn't matter what you do with the back end of it.
 
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Gearing Specs for SDR/GT are the same

This has been some very difficult information to obtain for some reason. But from what I can dig up they both run a stock 17/38 sprocket set up and share identical transmissions.
https://motoperf.com/motorcycles/KTM-1290-Super-Duke-R-2014-926667
This is correct..... I noted down all the gearing ratios from this link and compared them to my owners manual for my 17SDGT.

Also, I found a spec comparison on line by our Aussie AMCN where they stated the SDR & SDGT 16-18 had identical gearing & final drive ratios....... the only difference that explain's why SDR's are more wheel happy than SDGT's was the Gt weighed more - 233kg fueled vs (from memory) 198kg for the SDR.

I couldn't find any data on the 2019GT but I have read it has a number of changes to the engine over the prev model, mostly to do with titanium valves (from the SDR) and a heavier crankshaft than the SDR, with different suspension software & engine maps to suit the touring orientation.

In any case, my SDGT was awkward in certain situations (which I had no difficulty compensating for) but I wanted it to be better so I set about dialing my bike in to suit my riding conditions. As @AusPete writes, the 19 ECU upgrade may be a big factor too as the old maps were a bit sudden..... My baby is sweet as now :smile2:.

I might have another go when it is time to put a new chain and sprockets on (but that will be in a year's time from now). So I'll just have another quick change test of the 38t rear and see if my perceptions alter...... hell, with my new HDESA 60/40 sex tool on order from the USofA I might even be equipped to swap back to the 17t front if I get serious enough to return to the acceptable 17/40 sprox's :laugh2:.

I think the owners manual specs 130Nm for the front sprox..... so that's do-able with my tools.:grin2:.

Important PS...... if you are changing the rear sprox..... the pretty side (machined) goes facing the brake rotor, and the plain (rough looking) side faces out to you (a pity as the other side is very nicely finished). This is to line up with the drive sprocket...... it has tricked a number of DIY installs so take the time to inspect..... and check the oval lugs fit into their oval recesses on the back side of the sprocket/hub. Naturally, a low km bike will be a very tight fit for a 40T so make sure the chain is fully slack, and fit the sprocket into the chain first before attaching to the hub - you may have to do a coupe of 000kms riding to stretch the chain slightly - I was a late starter when I did this with 10k kms up :wink2:.
 
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I'd like to try a 40T on my 2017 SDGT. My local dealer parts man says KTM does not have one.

Can somebody please point me in the right direction to buy one?

Thank You!
 

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Cheers @bcdave,

Correct..... KTM does not have a 40T...... Supersprox does :wink2:.

My local KTM dealership parts guys ordered that in for me so I didn't have to pay freight from the USA to Aus, so somebody in Aus is importing them for stock.

errrr if you are in the USofA you can order from Supersprox direct with cheap freight (?).

:smile2:

PS If you decide to change the front to a 16t, then buy the KTM sprocket as it has the dampening material and costs only a small $amount more than an accessory 16.
 

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I can't imagine having lower geared at low gears... Why do you need to use 6th? 5th feels perfect at 100kph or 60mph. But when you get up to 75mph on freeways here in the states trust me you want that tall 6th gear. Gearing these bikes any lower at the low end is asking for trouble imo.
 

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Thank you DaveAu

Re: the 40T/16T . I think the wise way to go is to give the 40T a go at it first.

By the way, I'm in Canada. Sorry, I just haven't figured out how to Add that to my information box yet.

History: Been riding over 50 years. I'm sure well over 300,000 km's by now.
1 - NSU
2 - Harleys
4 - BMW's
1 - KTM SD GT

I tend to buy them then ride them for many years.
I've had this KTM for almost one year now. Only have a little over 10,000 km's on it so far.

I'm really loving this bike.
And, thankful for this forum.

Thanks to all of you!

bcdave
 
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