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Discussion Starter #1
i started the install for a hc2 on my 2005 R tonight. for the most part its going smoothly. i got the old cam out and the new one in. i bolted up the cam assembly and torqued the 4 bolts to 10 ft-lb. i tried rolling the cam a little back and forth to see if things were in there smoothly, but its acts like its in a bind? i'm not rolling it completely over, just like 1/8 turn MAYBE-- just the same amount i could with the old cam (not forcing it just going with the free play it had), but the old cam seemed to roll really smoothly. i took the bolts back off the assembly, but left it on the bosses and tried again and it seemed to roll fine. bolted it back up, and still really rough. is this normal? it is a used cam, but it has <10 hours on it so i dont think thats an issue.

my valve clearances seemed way off too once i had it all bolted up. .007" and .004" for the exhaust valves. and i am having a really tough time checking the intake valves. i've been using a straight feeler gauge, do i need to just go buy an angled one tomorrow?

also-- just want to double check i've got the cam in the right position to put it back in. the lobes are pointing towards the rear, slightly up. it seems like the exhaust rocker and decompression lifter are whats holding everything up. they dont seem to be moving much.

i dont know what to check-- snap ring, something on the side over by the decompressor bolt on the assembly?

i can't work on it anymore tonight will the engine be alright just covered up with shop towels in my garage for tonight/tomorrow?

thanks for the help,

Eric
 

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okay,

did you set your valve clearance? .04 and .07 was both before and after the cam swap?


did you pull out the cam carrier when installing the new cam?
if you did make sure the shim isnt out of position. if it fell out the pocket it sits on its gonna sit on top of the ring and push the bucket up. therefore making the cam harder to turn.


check to make sure all your timing marks line up.
 

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when we installed my brothers hc2 it did somthing similar, it'll turn freely in the carrier off the head, but when bolted and torque'd down it seemed to be in a bind. but we jus worked it back n forth a lil bit and if freed it up a good bit.

dont know if it was as tight as yours may be, but jus a thought.
and yea get ya a set of angled feeler guages, haha its still hard to check em but makes it alot easier than using strait feelers!
 

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Pull the buckets off the intake springs and put the carrier back on and see if it spins freely. I'll bet your intake valve lash is too tight and the bind you feel is the cam trying to open the valve too early. That's also probably why you're having trouble getting the feeler gauge to work on the intake side. A straight feeler gauge will work just fine. At least doing it this way you'll know for sure if there's another problem or not.
 

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with cam and carrier out of engine.....cam should be able to spin over 360* FREELY

with cam and carrier installed.....cam should be able to spin FREELY....up until the lobes begin to push on either the buckets (intake) or rocker arm (exhaust)....

two things usually hinder this.... well, actually three...

#1.....bad installation... something was not installed correctly....

#2....everything installed correctly.....but shims are just too big and need to be reduced. this is putting some pressure on your cam, before even trying to compress the valve springs...

#3... .cam was installed facing downward....not upward-rearward....this puts a tremendous amount of pressure on the cam and it usually wont spin at all.....


im betting on #2.........
 

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Discussion Starter #7
with cam and carrier out of engine.....cam should be able to spin over 360* FREELY

with cam and carrier installed.....cam should be able to spin FREELY....up until the lobes begin to push on either the buckets (intake) or rocker arm (exhaust)....

two things usually hinder this.... well, actually three...

#1.....bad installation... something was not installed correctly....

#2....everything installed correctly.....but shims are just too big and need to be reduced. this is putting some pressure on your cam, before even trying to compress the valve springs...

#3... .cam was installed facing downward....not upward-rearward....this puts a tremendous amount of pressure on the cam and it usually wont spin at all.....


im betting on #2.........[/b]


yeah, it spins freely out of the engine. i'm hoping its #2. i'm pretty sure its not #3---had the lobes upward and rearward. any certain spot i need to have it at besides just up-rear facing?

starting back on it in a little bit. we'll see how it goes.
 

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with cam and carrier out of engine.....cam should be able to spin over 360* FREELY

with cam and carrier installed.....cam should be able to spin FREELY....up until the lobes begin to push on either the buckets (intake) or rocker arm (exhaust)....

two things usually hinder this.... well, actually three...

#1.....bad installation... something was not installed correctly....

#2....everything installed correctly.....but shims are just too big and need to be reduced. this is putting some pressure on your cam, before even trying to compress the valve springs...

#3... .cam was installed facing downward....not upward-rearward....this puts a tremendous amount of pressure on the cam and it usually wont spin at all.....


im betting on #2.........[/b]


yeah, it spins freely out of the engine. i'm hoping its #2. i'm pretty sure its not #3---had the lobes upward and rearward. any certain spot i need to have it at besides just up-rear facing?

starting back on it in a little bit. we'll see how it goes.
[/b]

did you secure the cam sprocket to the frame with like a zip tie? cam bolts should line up in there right away.
 

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Discussion Starter #9
chain ziptied to the sprocket, not to the frame though. when i let the decompresser out it seemed like it held itself up and out of the way.

last night when i first posted this, i did not have the sprocket bolted onto the cam when i was having these issues. should it be bolted up if the assembly is in and i'm trying to roll the cam at all?
 

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chain ziptied to the sprocket, not to the frame though. when i let the decompresser out it seemed like it held itself up and out of the way.

last night when i first posted this, i did not have the sprocket bolted onto the cam when i was having these issues. should it be bolted up if the assembly is in and i'm trying to roll the cam at all?[/b]
there are 2 marks on the right side timing .. one is on the nut and the small one is on the gear the one on the gear is the mark to use... ive seen this alot...
 

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yea i think the most obivious thing is beig overlooked, check the cam timing make sure the makrs line up perfectly and when you look at them look at the straight on level not from a angle

get them shimmed correctly, and for the feeler gauges, just bend the straight ones to a anlge to check because they can be bent back
 

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Discussion Starter #12
i took the buckets out and could finally get a feeler gauge in there--- so it was just a matter of shimming/reshimming until i got everything in spec.

when i got everything back together and rolled it out to the driveway, i gave it 2 or 3 kicks and then it backfired... 2 or 3 kicks and another backfire... another couple kicks and it fired up. is this normal? seemed to be running strong after that.

i appreciate all the help, this forum is loaded with resources.

Eric
 

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any takers, backfires normal before starting? or do i have a problem there?[/b]
Doesn't this sound like a timing thing or maybe an exhaust pipe loose?
 

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to answer some questions....

Backfires are not normal...

Cam and Valve clearances should be checked BEFORE installing the cam gear and chain, etc.....

timing marks....either crank or cam timing have no bearing on your valve clearances or the issue of the cam not rotating freely.....



once all is accounted for...and cam/valves are now shimmed correctly....... RE-check your cam timing...... make absofrickenlutely sure your crank timing.....(using the inspection plug on the right side case) is aligned perfectly... as is your cam gear timing marks aligned with the cam carrier marks..........

it is very easy to be off one tooth +/- if you do not view these timing marks at eye level..... looking either upward or most likely...downward at this marks....can cause issues......... everything should line up perfectly....if you feel as though any of those timing marks were.....lets say......'in between'....... then check them again....... it is a relatively easy procedure...but sometimes having someone that has performed this task before to assist you will greatly help.......


good luck.....me~
 

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Discussion Starter #17
it backfired before start up, hasn't done it since then though.

do i need to check timing just on the transmission side of the case or do i need to pull the valve cover and check timing on the chain/sprocket too?


i could be wrong---i've been calling it a backfire, but then engine never started when this happened. after a couple kicks it popped. couple more kicks then it popped again. is this a backfire? or is a backfire only after the engine has been running and you kill it/then backfires?
 

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Discussion Starter #18
i just went out to mess with it some more. 2 kicks and it started just fine. i killed it right after it started, seemed like everything was fine though.

should i still be worried about anything?
 

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nah....sounds like you have a handle on it.....

a continuous backfire when you try and start a machine usually indicates some type of bad timing during assembly...

in your case...it may have just needed to 'clear its throat'.....

if all is good....and the power is good..... enjoy....
 

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i just went out to mess with it some more. 2 kicks and it started just fine. i killed it right after it started, seemed like everything was fine though.

should i still be worried about anything?[/b]

sounds like settup ready to ride.
 
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