So what is the perfect sprocket combo for an AT hack rig?
I may, after much experimentation, have the answer.
I had ordered a 15 tooth front sprocket to replace the factory 16 tooth, and had it sitting on my bench. An opportunity came up on short notice to do quick 330 mile round trip up to Congress, AZ and meet a fellow inmate to exchange cash for a set of Bumot pannier racks. I had been casually looking for a set ever since Miles, @Flying Monkeys gifted me a lovely set of Bumot soft bags, tailored for the AT, and couldn't resist the price.
So the trip came up on about 12 hours notice. I decided it might finally be time to swap out my barely used rear tire for a new one, do the rear brake service, and swap out a front sprocket that had a little wear after 12,000 miles or so in the sand.
Light desert use:
New Mitas E07+ Dakar.
So at after a nice full day, I wrapped it up for the evening and took a quick test drive.
The 15 tooth front, combined with the 45 tooth rear finally released Black Betty's inner hooligan! Hit a right hand turn, nailed the gas and expected to pick up the chair. Instead, was treated to a paved powerslide around the corner. That was something new!
Ran down the highway and checked speed with GPS. Speedometer error had increased to 8mph over at indicated 65. That is about what the math suggested would happen, so no surprise there.
Found that 6th gear was suddenly more useful at actual 80mph. Before it would not pull from 6th to pass, required a downshift. S2mode became useful, and S3 seemed just a bit revvy now. Before S3 was about the only tolerable setting on the DCT.
Next morning, did a highway blast out to Congress. My fears that the gearing would be too deep were unfounded. 6000 rpm was good for a GPS indicated 92mph in 6th
I think the hack drag coefficient would still keep one from pulling redline in 6th, but the potential is there now.
First gear now launches off the line with vigor. I think it will be much nicer for picking my way through rock gardens and steep downhill.
I suppose the downside might be a little more fuel consumption, either the need for a Speedo healer (or not) and the potential to replace a front sprocket a little more often, but im OK with that tradeoff for the over improvement in riding experience
