timing chain and chain guides

[4WheelinDemon]

Just dropped in my stage 3 hotcam. guides are worn down though BADLY. like its torn to shreds. now, i bought the 2002 CRF450R timing chain. should i get crf450r timing chain guides? or buy new OEM 2003 400ex timing chain guides? i dont want her to jump off track again and break. because i broken timing chain leads to a very non-happy day lol

help is appreciated. Thank you

[hocman123]

u can go with the stock guides for the 400 they will work just fine.

[4WheelinDemon]

are you sure? because ive noticed that the crf450 timing chain is a bit widder than the 400 timing chain.

[hocman123]

yes i am sure it will work me and many people i know have done it that way and its fine, i dont think the crf ones would even work right

[CJM]

x3 use stock 400ex ones. While your at it check the tensioner-it doesnt spring back well replace it.

[4WheelinDemon]

Ok stock it is. And ive pushed on it a couple times and it doesnt spring back. So i should just get a new tensioner? What do they usually run as in price?

[CJM]

about 60 dollars, yes you need a new one if it doesnt spring back.

[4WheelinDemon]

Cant i just take it apart and replace the spring/mod it? Im good at moding and repairing. I can get parts made for it if i need since i go to a trade school and there is a machine shop were i always machine things. I just got an aluminum plate the saze of a license plate engraved with my username 4WheelinDemon lol its badass.

[CJM]

No, you need a new one. Its not repairable as far as I know. You could try if you want tho.

[2001400exrida]

Originally posted by CJM
No, you need a new one. Its not repairable as far as I know. You could try if you want tho.

first of all your tensioner may not be shot, the spring is definetly replaceable if you can find one like it that's all there to it.

I just recently took mine apart and it was the spring that was bad, i bought a new one unfortunately.

Anyway, you probably won't be able to just push on the tensioner. Basically, if it sticks out about an inch or so that's good. Now get a small flat head screw driver, remove the phillips screw in the middle of tensioner, and stick the screwdriver in there. Turn it counter clockwise until the tensioner comes back into the housing, then just pull the screwdriver out and the tensioner should pop back out.

there's no easy way to just push on the tensioner, especially if the spring is good, it's very hard to do. I just turn it with the screwdriver and then release and see if it pops back out, if it does you're good.

[CJM]

Interesting, never really took it apart to tell you the truth.

[CJM]

Interesting, never really took it apart to tell you the truth.

[4WheelinDemon]

ok so the spring was broken and coiled all up in one little piece jammed into the bottom having zero spring. now tell me this because i have a thought on this. cant i just make it fixed at a certain tension and lock it like that? here it is...

ill take out the philips and then ill turn the flat head screw counter clockwise until i reach a very resonable tension on the chain. after that, i can possibly stick my arc welder in there and make two small tacs in the hole where the philips screw goes in so it will hold that screw in place thus not pushing back that arm that pops out. i will be sure to not touch the threads for the philips screw though.
it will be stuck at a certain setting for good.
if i want to change the setting i can always grind off the tacs with my dremal drill and a ball head bit. ill grind them off and change the setting if i choose to.
conclusion being no spring needed. i personally do not see the function/purpose of the spring. if you push on that arm that pops out it will just go back in. and i know that with the added spring it is not hard to push in. if i just make two small tac welds it will stay. anybody see what i am saying? tell me if that sounds like a good permanent fix.

[hocman123]

i wouldn't do that. the reason it is a spring on it is b/c as the chain ages it will push out more to give u move life to the chain. I would be way to uncomfortable with out it i would be checking like every few rides like a nut. and if u don't tightn it regularly and the chain jumps u could bend valves and that would be a few hundred bucks. would be cheaper to get a new tensioner now then have to do that later

i also do not know how many times u could weld grind weld grind untill u would have to replace it anyway. and how do u know how hard the spring is if yours is broken i have held many of them in my hand that were working and it is extremly hard to push in with just ur hand. they wind that spring really tight inside.

u could if u want get a adjustable one on ebay that has a long rod with a nut on the end and a nut on the threads and u can adjust it by hand and u could do it really quicklly and i think they go for 30 bucks but i have seen spring ones go for 50 on ebay thats were i got mine.

[4WheelinDemon]

Ok than. How about this, can someone tell me how much tension the spring gives off? Like whats the spring pressure

[hocman123]

i have no idea

[4WheelinDemon]

Nevermind, i modded my old one. I made it a fixed position one. Pretty neat idea btw. Take a bolt thats a bit longer than the philips with same threw and put two o-rings on it. One big to fit over entire surface thats usually covered and a small one thats tight around the bolt. Have a nut and washer above those two on the bolt. Screw the bolt in AFTER you turn flat haed screw counter clockwise to desired tension and put about 20 foot pounds of torque. Then screw down the nut so it can seal and seat the o-rings. Honestly, it works pretty dam good too.

[CJM]

Check it for tension every 5-10 hours to make sure its enough as the chain can and will stretch over time.

[2001400exrida]

It might be working for now but that sounds like a good way to mess up some stuff.

I would honestly invest in a good tensioner, that thing may be little but it serves a good purpose. If the chain is slapping ont he guides then you may end up trashing your chain, guides, and tensioner, and possibly the cam sprocket.

[4WheelinDemon]

i will check it after every ride actually. And its honestly a really nice mod to replace a broken spring. look at it like this, you can adjust it to any tension setting you want. the chain will be tight. My new crf timing chain will not stretch anywhere near as easy as the stock 400 will. i will just put the correct amount of tension on the chain and then screw in that bolt i mentioned then screw down the nut and bolt on the bolt to seat the o-rings nice and tight. with that bolt screwed into the same place the philips does, it compresses against the flat head screw thus eliminating it from moving/loosening up. i will over time buy a new tensioner though, this is only for a temporary fixer upper until i get the funds for a new one. im just using it so i can now break in my stage 3 hotcam and get the piston rings to set. after all of those are broken in i will get a new tensioner.

and btw, about the timing chain sproket thats on the crank shaft right next to the oil pump...it is so worn down its unbelievable. the kid i bought this off of didnt give a **** about this quad. the clanking i kept hearing was from the timing chain having zerro tension. i thought it was the valves. but yeah, that sproket is worn down pretty bad so im buying a new one today at the cycle playground store in my town haha