Help with my brother’s Rhino timing gear deja vu

[Ash.Leigh365]

Fixed up my brother's 2008 Yamaha Rhino in Georgia after its decompression valve gave up on life midride. We dropped in new timing gear and related bits, fished all the junk out of the engine and it ran like a charm... until a few rides later it started acting up again. It's not exactly on a sched but the issue creeps back once it's had time to lull us into thinking it's fixed. Has anyone tried replacing the cam too or looked into deeper valve issues?

 

[ch33s3_whz]

Fixed up my brother's 2008 Yamaha Rhino in Georgia after its decompression valve gave up on life midride. We dropped in new timing gear and related bits, fished all the junk out of the engine and it ran like a charm... until a few rides later it started acting up again. It's not exactly on a sched but the issue creeps back once it's had time to lull us into thinking it's fixed. Has anyone tried replacing the cam too or looked into deeper valve issues?

I've helped my cousin with the same issue. When the decompression mechanism goes, it can sometimes mess up the valve springs or the rocker arms without it being immediately obvious.
try to pulling the valve cover again and giving those a close inspection to make sure it's not causing the issue

 

[Ash.Leigh365]

I've helped my cousin with the same issue. When the decompression mechanism goes, it can sometimes mess up the valve springs or the rocker arms without it being immediately obvious.
try to pulling the valve cover again and giving those a close inspection to make sure it's not causing the issue

We didn't look too hard at the springs or rockers the first time since the timing gear was the obvious mess. I'll crack the valve cover again next weekend and see if anything's off or worn. If we do end up needing new springs or arms, did you go OEM or aftermarket? Trying to keep downtime short so we're not stuck waiting on parts.

 

[Sandman]

If the decompression valve issue keeps returning, a worn cam lobe or related valve train wear could be causing it. Have you inspected the camshaft and rocker arms closely for damage or excessive wear?

 

[Ash.Leigh365]

If the decompression valve issue keeps returning, a worn cam lobe or related valve train wear could be causing it. Have you inspected the camshaft and rocker arms closely for damage or excessive wear?

So either the decompression failure led to another problem, or we missed some wear earlier. We didn't inspect the cam lobes closely when we changed the gear, so we'll check them when we remove the valve cover this weekend. If the lobes are worn or the rocker arms appear uneven, we'll likely replace the cam as well. Did you use a stock cam or go with an aftermarket one with a stronger decompression setup? We're hoping to keep the Rhino out of commission for less than a week since my brother needs it for hauling feed and fencing gear.