KTM 990 SM-T | DOIN' TIME

Long-term update: Another set of tires?!

WRIST: Marc Cook

MSRP (2013): $13,999

MILES: 13,278

MPG: 37

MODS: Another set of tires!

Not all matches are made to be. After not too many miles on the new Michelin Pilot Road 4 sport-touring tires, I began to notice the KTM “tramlining” aggressively over certain surfaces found on my daily commute. This term describes a bike’s willingness to catch longitudinal grooves in the pavement, which then causes it to change lines without rider input. I’d noticed a similar trait on the BMW R1200RT testbike we had, which also carried the PR4.

I was curious to see if this is a tire thing, so I swapped the Michelins for a set of Continental RoadAttack 2 tires I had around for another project. On the Contis, the KTM tramlined no more, suggesting an interesting and undesirable tire/bike interaction.

Also on the topic of tires, I got excoriated by a reader who said I should be trying more of the 90/10 (street/dirt) ADV tires than sport-touring rubber. After reminding him that the SM-T is really a streetbike built from an adventure-tourer’s bones and that it carries pure-street wheel sizes, he confessed that he must have been thinking of the 990 Adventure. But it’s worth making the point again: There are relatively few 90/10 or 80/20 tires in SM-T’s sizes. Many, many more if you have a 19- or 21-inch front. If you want to go off road with some regularity, a 990 or an 1190 Adventure would be a better choice.

Located in the rear header pipe, the gasket suspected of leaking was exonerated by inspection.
All the visible damage came from removal. No need to have worried.

I left off last month planning to fix what I thought was an exhaust leak at the joint between the rear header and the rest of the exhaust. After disassembling the system and inspecting the joint, it’s obvious that the discoloration I’d seen was the result of junk thrown up by the rear wheel and not an actual exhaust leak. There’s a collar on the head pipe meant to help capture the “graphite ring” gasket, and it was plain that the discoloration did not extend down below that collar in the direction of the joint. What’s more, the gasket itself showed no signs of leakage.

In all, it took 90 minutes to partially disassemble, inspect, and reassemble the system, a task I’d rate a bit harder than some Japanese bikes I’ve owned but easier than on my old first-generation, twin-cylinder Aprilia Tuono. I wish the KTM had a more effective hugger; the miniature stock item lets the rear fender and exposed exhaust wye get really grungy. A small gripe, I confess, that’s totally forgiven in the first half mile back on the road. Especially now that dry summer weather is here.

Next up: I’ve just begun riding with KTM’s accessory Ergo seat, which has a gel insert. I really like the stock seat, but it’s always worth trying alternatives to see if you can do better.

More Doin' Time: KTM 990 SM-T

Located in the rear header pipe, the gasket suspected of leaking was exonerated by inspection.
All the visible damage came from removal. No need to have worried.