I swapped the front sprocket on my Scrambler to a 14 tooth today, weather is diabolical so I can’t get out to try it, I took note of the revs at an indicated 70 mph yesterday, 4K and 2 bars (about as accurate as I can be with the stupid rev display on the scrambler) this was with the original 15 tooth sprocket fitted, has anyone already changed to a 14, I’m wondering how many more revs it will be doing at 70 ?
Feck me! It must rev like buggery. I couldn't thol the standard gearing and went for a 44t on the back. Check the revs on gearingcommander.com
Ha, it’s a bit of an experiment, the thing is I tend to use it on the country lanes around here, short straights lots of tight corners so I’m looking to improve the acceleration , for long trips I use the 900’s or 1200, I’ll have a look at the calculator thanks, (I’m guessing another 400 revs but let’s see).
It's pretty simple really. You select the brand - DUCATI, the model - Scrambler, the Variant - 803. The enter your sprocket sizes in the CURRENT or CUSTOM in the table with the values for front and rear sprockets. This is the table with OEM, 14/46 and 15/44 values. And scrolling further down, this shows the RPM differences. As you can see, at 70mph the 14/46 is running 354rpm faster than standard while my bike at 15/44 is running 574rpm slower than standard. So my bike is running over 900rpm slower than yours at the same speed.
Thanks Derek, I knew if I waited long enough someone would do it for me! , my guess was pretty close then only 46rpm out, I’ll see how it feels out on the road, usually the only time I hit 70 and above for any distance is on a 2 mile stretch of dual carriageway on the way to my local Starbucks, in standard gearing it feels a bit buzzy so I understand why you’ve upped your gearing, on the back lanes that I ride it on I want to see if lowering the gearing as I’ve done allows me to remain in 2nd on some of the really tight corners, I’ll probably end up returning it to standard though!, reading other forums people are pleased with the results moving the gearing both up and down, horses for courses!.
Well it finally stopped raining long enough for the roads to dry so I’ve been out, I expected 1st to feel really short but it doesn’t, 70mph in top shows 2 more bars on the Rev counter, it feels fine at that speed, no more buzzy than before really, where I can mainly feel a difference is in mid range pick up, because I am at slightly higher revs at a given speed I suppose , so all in all I’m happy with the swap, I might however replace the 15t front and get a 48 tooth rear sprocket, mainly because I fancy one of those new fangled alloy centred jobs, might need a longer chain though so that’ll add to the cost, hmmmm!
Well not that new fangled rear, something along these lines https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/293142749260
just bought it, would’ve preferred silver but they were £46, I can always spray the red bit if it looks too gaudy. PS as an experiment I’ll leave the 14t on the front initially and see how it rides, that should get the revs up!
Nice bit of kit for £36, I’ll get it fitted tomorrow if I have time and report back on how 14/48 feels (like a trials bike?), if I have to go back to 15 on the front I’m hoping the chain will be long enough but it probably won’t!
Can't say I'm enamoured of the colour or the squarish holes Mark but with a 1 tooth change at the gearbox sprocket the chain should be ok. With the OEM sprockets I went from a 46 to a 44 at the rear without shortening the chain, although it is getting near to the end of it's adjustment.
Gearing Commander to the rescue again. You can see that the sprocket centre distance only reduces by 3.66mm going from the current (14:46) to stock (15:46). In my case it increased by 7.33mm in going to a 15:44 set up. So I don't think you'll have any problem
when you say "acquired" i think you mean bad..... lol... if you want to do a proper back to back you should buy my scrambler as well coz its still got standard gearing!
Maybe it’s just my newly acquired bad taste then!, the plan is see how it looks on the bike and paint it out if it looks too crass, have you put your bike up for sale anywhere but this forum yet Chizel?
Yes, I’m not immediately loving the look, the Matt black spray (or silver) might be coming out soon Hopefully get out for a run on it tomorrow if the weather forecast is to be believed.
