Destructo 12 Posted May 18, 2022 Decided to rip down the top end, clean everything up and inspect every part along the way. Got to the cam and noticed the decompressor does some strange things however I'm new to these little motors and haven't had the glory of inspecting a decompressor cam like this before. I have attached a video, could somebody let me know if this is how this cam is supposed to work or is it "loose"? If i push on it as told to by the honda manual and its not perfectly normal in orientation it gets blocked from its closed position unless i tap it slightly to either side...as seen in video. The springs feel VERY soft it takes very little force to push the decomp down. 20220518_070759_77760405069241.mp4 Share this post Link to post Share on other sites
Destructo 12 Posted May 20, 2022 @shadetree I'm sure you've seen a zillion of these... what do you think? Is this how its supposed to operate, or does it need to be replaced/chopped off etc. A Little pre info- the motor made a somewhat loud ticking noise as if the valves were slappin' but i set them correctly as per the manual, the crank has about .0005 play in it and the piston wrist pin was good, also no pertinent play in any direction. my cylinder hone broke, so i ordered a new one... the new valves are taking forever to lap but once that's done and the cylinder is honed id like to slap this baby back together. Just cant seem to find a whole pile of info on this decompressor cam other than the uber-rudimentary-lack-luster instruction in the manual. Sorry to bug, but please consider it a sign of respect to your experience and knowledge base. Share this post Link to post Share on other sites
shadetree 5,880 Posted May 20, 2022 18 minutes ago, Destructo said: @shadetree I'm sure you've seen a zillion of these... what do you think? Is this how its supposed to operate, or does it need to be replaced/chopped off etc. A Little pre info- the motor made a somewhat loud ticking noise as if the valves were slappin' but i set them correctly as per the manual, the crank has about .0005 play in it and the piston wrist pin was good, also no pertinent play in any direction. my cylinder hone broke, so i ordered a new one... the new valves are taking forever to lap but once that's done and the cylinder is honed id like to slap this baby back together. Just cant seem to find a whole pile of info on this decompressor cam other than the uber-rudimentary-lack-luster instruction in the manual. Sorry to bug, but please consider it a sign of respect to your experience and knowledge base. yes..that is how they work. as for the ticking ?, unless you are not adjusting the valves on the correct stroke ?, i'd say the cam chain needs replacing. is this a trx500 rubi ?, i have not worked on many of these models, why ?, because most are automatics ?, or es ( electric shifts ) ?, and neither of them do i like one bit !..lol. if its a fm ( manual shift ) ?, then i know a tad about these models. be warned !!..the early trx500fm's came from the factory with a bad first gear design !. Share this post Link to post Share on other sites
Destructo 12 Posted May 20, 2022 yes its a 500 rubi es ... I too hate the hondamatic shenanigans but i couldn't resist 2 working quads for 4k this far in the north.. typically a broken one that needs a ton of work is that price. i set it on the correct stroke. however thank you, i have a chain on the way anyways and a brand new oil pump ( the upgraded one) so i guess i may as well pull the bottom end and slap that all in there before the deer season opens up haha just glad that this cam isn't toast. Share this post Link to post Share on other sites
