Join Date: Jul 2018
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From awesome to oh crap
2011 Brute Force 650 4x4 KVF650DBF
Ok, so I 'm a very recent (7/12/18) new member. I posted yesterday asking about backfiring and lean running carb (titled-engine backfires and carb issue). Through the advice of one of the mods and doing some more research (youtube) I fixed those issues and the engine on the atv is running better than ever.
After putting all the covers and cowlings back on I go for a test drive. I kept my aftermarket tach, which I use for a tool, on it during the run just to understand what rpm at any given speed the atv is doing. So I am running it up and down the county chip and seal blacktop road and all is going well. Towards the very end of the test drive I look at my speed and rpm which is about 42mph at roughly about 6200rpm. I notice I haven't even hit half throttle so, like an idiot school boy, I gun it.
Yeah I know, using the wise words of Bugs Bunny, "Ha ha! What a maroon!".
After gunning it and about 10-15 seconds later there's a *pop* and a *blpblpblpblpblpblp* while decelerating. When I hear the pop I knew I had blown the engine and looking down at the gage cluster I get a confirmation with a tale tell sign of a flashing red oil light, granted the light came on AFTER it popped, but on nonetheless. After coming to a stop, confirming that yes there indeed is proper amount of oil, and hitting the starter button, I get a sluggish cranking and what sounds to be like low/no compression confirming something bad happened.
So here I am at the computer telling my tale and cooling off and shaking my head while finding out that my warranty on the engine is out.
So while I cool my jets before digging back in to it to see just what exactly blew and happened, let me ask a couple of questions since all of my mechanical experience is on aviation and automotive and not on atv.
1)Is that rpm for that speed high?
2)While for the automotive world 6200 rpm is redline, for the atv and motorcycle world even if the engine reached 6800-7200 rpm's before it blew that shouldn't have been redline excessive would it?
3)For future reference what would be the upper limit rpm range be?
4)The "red" belt service light was on and I had a belt on order cause I noticed a chunk missing in the outer ribs. It pulled alright before so while it was being shipped I decided to keep running with it. With this light on does it somehow lock the drive converter pulley into a low range mode?