Guys, I genuinely need some help because I’m completely fed up with this bike and the service centre at this point.
I have a BS4 Interceptor 650 and this whole mess started after I got the bike painted and also got the engine buffed.
The original problem was mainly when the bike got extremely hot, especially in scorching sunlight. It would start losing power, eventually stall, and then I’d have to wait for a couple of minutes and give it a hard throttle while starting to get it moving again. Even after starting, it wouldn’t rev beyond around 3k rpm.
The bike went through multiple checks and parts have been changed since then.
The service centre has:
Changed the fuel pump
Checked/replaced the magnet coil
Replaced the ignition coil
Replaced the O2 sensor (multiple times)
Replaced the fuel injector
Replaced the throttle body
Replaced RR unit
The throttle body situation is where things got interesting.
The original throttle body was removed for cleaning. But while reassembling it, the stopper screw was found to be rusty/faulty and apparently couldn’t be properly reused/adjusted. Because of that, they ended up replacing the entire throttle body.
The new problems started after this throttle body replacement.
Now the right cylinder is clearly misfiring.
On a cold start, the right exhaust/header is noticeably cooler than the left and the exhaust pulse is weaker. Once the bike warms up, both sides become more similar, but every now and then the right cylinder still misses a pulse.
During one test ride, the right exhaust actually went almost completely silent while the left cylinder was still running.
On top of that, the RPM randomly hangs after I give the throttle. It can get stuck around 3-4k rpm or sometimes at other RPMs. There’s no fixed pattern at all. Sometimes it happens, sometimes it doesn’t. If I roll off and give another throttle input, it can suddenly go past that point.
The initial throttle response is also terrible compared to how the bike used to be.
The bike has also been dyno tuned at some point. AFR was changed and pops were added around 4k rpm, so I’m also wondering if the tune could be contributing to some of this.
The really frustrating part is the service centre situation.
It’s been around 3 months since they started looking into my bike. They don’t even work on it continuously. They’ll take the bike for a week, then basically nothing happens, then I get some vague answer. Sometimes they take it once in a week and keep it for another week.
I’ve been getting different explanations and parts being changed, but nobody seems to be able to actually tell me what the root cause is.
At this point it feels like they’re just doing trial and error with my money.
I’ve been patient with them for months, but I’m honestly tired of hearing “we’ll check it” and then getting the bike back with the same problem.
So I’m hoping someone here who actually knows the 650 engine can help me figure out what I should be looking at.
If the right cylinder is still misfiring after the injector, ignition coil, O2 sensor, fuel pump, magnet coil and throttle body have been checked/replaced, what would you check next?
Could it be:
Wiring/connector issue?
Intake leak?
Valve clearance?
Compression?
Throttle body/TPS calibration?
ECU/tune?
Something mechanical?
And has anyone experienced a similar intermittent one-cylinder misfire + random RPM hanging on an Interceptor 650?
I’m honestly just looking for some direction because the service centre guys seem to be going around in circles.