In my previous review of the 2021 Royal Enfield Interceptor, I had alluded to the ability to upgrade this lovely piece of work that the boys in India have given us. I had the dealer install the S&S slip on pipes (with baffles…I don’t hate my neighbors that much), and I had swapped the air filter for a K&N with a DNA airbox eliminator. This had made her a bit beefier at the altitudes we right here in New Mexico (between a mile and two miles up) and she could reliably hit the ton in 6th gear.

Next up was cosmetic fixes — Hitchcock bar end mirrors in stainless and black shorty levers to go with the short RE flyscreen, and a little tool bag for some kind of storage. But the big mods were still forthcoming: I decided to have the S&S high-performance camshaft installed, as well as their high-compression pistons. Why? Honestly, I don’t know; I’ve never done anything to modify an engine before. I figure the engineers are more experienced than I am, so leave well enough alone. But I sensed she could be more…

The local dealer has just picked up Enfield, but they have built race bikes before so I felt fairly confident they could do the job. The labor was about eight hours on top of the parts, or about $1500 out of pocket. After researching about i was fairly confident we could squeeze about 15% more horsepower and torque out of her. When I got it back, the low end torque and power was brilliant! Then I took it up the Sandia Crest road (where these pics were taken.) It’s a climb of about 4000′ over ten miles with 120 turns in the road. On hard acceleration up the mountain, she was rattling and sounding like she was going to come apart. Then she cut out. The bike fired right back up, but had to be ridden very gently. Even at highway speeds (out here that’s 70mph), she was getting detonation.

Back to the dealer. The timing was off by quite a bit, so if you do this, the cam does not line up as it would with the original cams. Have your mechanic (or you) do a timing wheel to make sure. Once that was done, we were able to pull 115mph indicated out of her. Low end torque is brilliant, and she dusts the stock Continental GT my friend has in acceleration. However, she was still getting light detonation with heavy throttle in 5th or 6th gear once she got hot. i threw some octane booster on top of the 91 octane I use (the best we can get easily in NM) and the problem occurred rarely and only when really hot. She’s also picked up a rough idle and gets all Ducati about starting in the morning. Some of this was further mitigated as our state went to “summer gas” — the ethanol content drops about this time of the year — and the octane booster hasn’t been needed. So it seems to be a fuel/air mix issue now — no surprise since the compression got bumped to 11:1.

I hadn’t heard it for a week, then we took the bikes for a long 150 mile run that included a lovely stretch of arrow straight road — flat as can be — that rarely has traffic. Going for the ton with a quick throttle snap and there it was; bad enough to start losing power. Downshift to 4th and hammer it got me to the ton before a quick double shift up to 6th and while you could heard the detonation, she still hit 110mph into a strong wind with my heavy ass on the bike.

The next step is to get a Power Commander 5 on her and see if we can pull the O2 sensors to get a good autotune on her. S&S and Dyno don’t have a map for this configuration, nor does Powertronics. Dyno-ing her isn’t really an option. There’s no dyno in Albuquerque who I’d trust with her, and the nearest is a 5 hour drive to Farmington.

So is it worth it? On the camshaft, I’d definitely say yes. Even with the fueling issue, it’s pulling like a tractor at low RPM (about 2500-3000) and where it would top out about 100mph and 6500RPM, she’ll run out to the redline and still has more. On the pistons? I’d shy away from this until someone has built a reliable map (hell, that might be me, soon…) You’ll save a lot in time and/or money and still get plenty out of the bike without the finicky fuel issue.

Update: It looks like we’re going with the Power Commander V route, and the dealer is going to split the cost for a dyno run with me to clean up the fueling/timing. That means they will probably have a map for sale once we get this sorted out in June.