416 Valve Noise...

[timp224]

I just took my 416 out today for my first long trail ride. I have a 2007 bored to a 416 11:1 wiseco, xr 400 head gasket, stage 2 hotcam, 450r carb full exhaust, open air box. I noticed about 30 min into the ride that while low in gear if I hit the gas i would hear a valve noise. It only occured while in higer gears, while under a bigger load. Im not sure if this is because of the octane im running, i have been using 93. The quad also seemed to be losing a little power towards the end of our 2 hr ride.

[NMills]

You noticed it in a low gear???? but it only does it in a high gear??? i'm a bit confused...

[CJM]

Im also confused, by what you mean that it occurred in both high and low gear.

If its in low gear it could be your drive chain, mine will make that sometimes when Im in to high a gear and lugging around.

[slightlybent47]

The valve lash is going to be a bit louder with the new mods. Try bumping up the octane a bit and see what it dose. U4.2 is 105 and is a direct pore in so there no mixing. Put a gallon in and ride it, see what it does.
I had to get use to the tapping when I did my mods, I kept thinking it needed adjustment but it always checked out when I gage it.


Could be just bad gas, sometimes 93 is really regular, sometimes when there out of 93 they’ll put regular in and sell it as premium.

[slightlybent47]

By the way I know someone that drives a tanker and according to him it doesn’t mater where you fill up, Exxon, Shell, Shamrock, where ever. It all comes out of the same tap, he fills up from one tap and delivers it to deferent stations and they sell as there brand.

[timp224]

When i said low in gear, i meant if i shifted into gear and then gave it a lot of gas while the rpms where low, it would make a clinking noise from the valves. I also noticed this noise when going down the railroad tracks, when i was low in 5th, or at low rpms in 5th and hit the gas i could hear the valve noise. I think my gearing is way to high, I put a 15 on the front and a 36 on the rear. But reguardless i dont think i should be hearing this noise.....

[timp224]

Oh yeah, i know a ticking from the valves is normal with the hot cam, this is not just the norm ticking. If you have ever gone a long ride with you ex in the woods and shut it off, or stalled it and then started it right up and heard a valve clank right when you started it, that is the noise i am talking about..... except i hear it when riding.....

[CJM]

Stretched timing chain, worn chain guides and or tensioner going bad.

Was any of that replaced when you did the rebuild?

[timp224]

I did install a crf450r cam chain during the rebuild, but didnt replace anything else.

[timp224]

I also noticed that it only was making this noise when the quad got hot, after about 30 min of riding.

[CJM]

Tensioner could be bad, take it off, stick a screwdriver in the hole after you remove the cap=springs back good, no spring bad.

Were the guides good looking, not chewed?

[timp224]

the guides look good, and i just did the rebuild about a month ago. I have only done the break in and the spring was good on the tensioner when i put it back together. I dont think it is the cam chain because after i got back from riding, i washed my quad and let it sit. After that i started it up and didnt hear that noise while riding it. Also while breaking it in i never heard that noise but i only was riding it for like 15 to 20 min at a time. This was the first long hard ride, it seems like maybe it was getting to hot, but im not sure. I just bought some 110 octane from a friend im gonna mix it 50/50 with 93 and see it that helps. Also I think maybe my gearing is too high for the woods (15 front, 36 rear). I think im going to go back to 14 front and see if that helps. Any other suggestions.....

[matts27]

Did you re-use the stock valve springs on the rebuild? If so, did you check em for height, free before putting them back on the head. Also, what are the valves adjusted too--- 6mm?

[timp224]

I did use the stock valve springs, didnt even touch the valves. The quad is an 07, didnt think they would be bad yet. But maybe aftermarket valves and springs woulnt be a bad idea

[timp224]

oh yeah valves adjust at 5, 6 mm

[CJM]

Sure its not your drive chain? Like I said when lugging in higher gears mine makes the same noise, tighten the chain to much and it goes away. How loose is your chain, should have about 1.5 inches of play when your off the quad.

[Choppers]

Prolly same problem I was fighting for month. Detonation. I ended up running race gas a few tanks and solved problem. I tried cham chain tensioner, guides and crf450 chain, re-did valve job. Same everytime. I am now rebuilding and going to 10:8:1 compression and 440. I had 11:1. Just to much I guess for the heat in Florida.

[timp224]

what do you mean detonation, is my quad going to blow up? I hope not, i just got the race fuel but havent had a chance to go for a ride. Hope that helps!!!!!!!!!!

[Choppers]

It can. Causes bike from my understanding to run lean. Can burn whole in the top of piston.