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Discussion Starter · #1 ·
Hello folks. I have an MV agusta Dragster RR 2015 from a friend. he did the oil change himself and installed the oil filter the wrong way around. anyway, the bike ran for about 30 seconds with no oil pressure. as a result, the timing chain jumped a tooth (camshaft outlet). I put everything back together and did a compression test. is ok on all 3 cylinders. pressure loss she has almost no. Anyway, the bike is very hard to start. I then replaced the starter. (carbon brushes were burned out). it's still hard to start. therefore replaced the starter clutch. still starts with difficulty and the fault memory of the ECU says: valve timing adjustment. the timing marks are correct as stated in the manual. I removed the cylinder head and sent it to an engine builder to be checked. the cylinder head is good. pistons are good. valves are not hitting the piston. If I turn the engine without the cylinder head, it turns easily, just like with other motorcycles. But as soon as I put everything back together and crank the engine by hand (without spark plugs) it feels too stiff. the starter has difficulty cranking the engine. I checked all plus and ground cables. I also put a jump starter on the starter. the motor is still turning slowly. camshafts are not broken in. the balancer shaft has an axial play of about 2-3 mm. is that normal ? do you think the main bearings are broken? I do not know how to continue. I would love to take the engine apart and disassemble it.
 

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Old Wing Nut
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If the engine was run without oil pressure, and the timing chain jumped a tooth, then your camshafts (or one of them) has seized in the head.
Camshaft bearing surfaces (the plain machined surface of the head) are one of the first things to get damaged when oil pressure is not present. For the timing chain to jump a tooth one of the cams must have momentarily stopped.
Take a photo of the cams and the head bearing surfaces for us.
I have seen this many times on many brands of bikes in my career. It is easy to put the filter in backwards on lots of different band bikes out there.
A galled bearing cap in the head will cause difficulty in turning the engine.
 

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Is it possible that due to lack of oil pressure for an extended period that the hydraulic cam chain tensioner flattened out allowing too much chain slack?

If an engine builder did a check on the head and missed a galled cam bearing I would be surprised.

By the way, welcome to the hard starting 2015 Dragster club (see the long post I just made).
 

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crank the engine by hand (without spark plugs) it feels too stiff.
Another thought - when you put the engine back together and cranked it by hand, it SHOULD have felt harder. The valve train on an engine takes considerable power due to the compression of all the springs. Given the stiff dual springs in these high revving engines and 4 valves per cylinder, I would expect quite a feeling of drag.

In college we had a lab where we tore down and rebuilt a 100hp 4cyl turbo diesel (out of a John Deere tractor). Part of the lab was to dyno the unit and measure frictional losses. We dynoed at full power and then used the dyno to just turn a non-running engine over to see how much power it took. If memory serves correctly, it was something like 20-25hp. And thats for a clumsy engine that redlines at like 4k.

Just a thought
 

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Discussion Starter · #5 ·
thanks for your tips. Yesterday afternoon I removed the camshafts and the clutch again in peace. When I turn the crankshaft I hear a slight grinding noise. I'm sure that the main bearings or the connecting rod bearings are defective. I'm putting a short video online today. I will remove and disassemble the engine over the weekend. I'll keep you up to date.
 

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Old Wing Nut
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Should be OK with just new bearing shells....the journals and rods do not look damaged and no excessive heat evident.
 
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