Hello everyone

Im new to this forum and to this bike. Love them both lol, i have 1998 vtr
that i picked up off a trade for my 2000 cbf F4. The bike needed alot of tlc but i got her up and running. i turned her on yesterday and notice a knock coming from the front by the gas tank, i ignored it and took it around the block and it would go away at high rpm's, but it got louder so i shut her off. Im new to v-twins but im a certifierd auto mechanic and have worked a little on i4 bikes. Ive been reading alot about the CCT on thesed bikes going bad. It did sound like if a chain was slapping but idk. I also though it would be valves but i dont see a reson why they would go bad. If its the cct did i damge the valves?
any help would be appreciated, thanks

 

Check if the timing is to spec (cam chain will jump sprockets if a CCT fails) and the valve clearances.

If you've got off lightly replace damaged valves and guides (or transplant second-hand head on) and fit manual CCTs to prevent a reoccurrence.

Also as you've got a '98 early model replace unfinned R/R with a later improved finned version / or upgrade to a MOSFET version.

 

i will do that as soon as i get off work, im going to take off the tank and start deconstruction. Thanks

 

HA! Anyone ever noticed the first 4 letters/numbers of the unfinned regulator part number?

 

lol, totally noticed that long ago.

It is ****...

 

i got a quick question, is there any possible way any at all that the cct failed and the noise i heard were the chains. It was a very loud knocking in sync with the rpm's Note, it got louder after i drove it and it sounded alot like the valves as it would in a car but the bike never lost any power it did backfire a little more though when i turned it on.

 

Do not start if you suspect CCT failure. When the CCT goes it will sound like a bag-of-nails as cam-chain claps around, jumping sprockets and valves bumping into piston!

Investigate before you potentially do more damage.

One thing that give a peculiar 'rattly' sound from the engine area is an airleak from the exhaust (either the header gasket / or where it connects to the link pipes) - or even on the move a loose dangling drive chain clapping against the exhaust headers check those out.

 

thanks i will do that, i just found it so weird it was a low knocking and then after driving it around a 1 mile area it was way louder and sounded like CLACK CLACK CLACK CLACK CLACK. im low on funds so im trying to find out the cheapest way to have it fixed or im just going to sell it as is which i dont really wanna do but i will have no other choice i hope its just the chain that is loose

 

Yeah, if it's perfectly in sync with the engine speed there is something bad going on. A loose DRIVEchain will not necessarily match revs. It also will tend to be louder at lower rpm and lower speed because the chain will tend to "float" at higher speeds and not whip around.

Have you checked the oil level? How's it look from the sight window, dirty or clean? I'm concerned it might be an internal bearing or something really bad.

 

Evil, where are you located? Loud clacks that match engine speed does not sound cheap... unless the exhaust thing turns out to be correct...

 

well guys i took off the carbs, airbox, fuel tank and valve cover. Before i took out the tensioner the chain was loose, like i literraly can pick it up and make it skip a tooth. I proceeded to remove the tensioner and the chain didnt even flinch, so im glad i found the problem. Hopefully no valves were bent, or any major problem. One thing i dont get is what is the bolt on top of the tensioner for. i didnt see no way how this tensioner would work, it doesnt come out or push in to tighten the chain. the bolt on the top is useless, is this normal or do i have some weird out of ordinary tensioner?

 

If I understand your question, the tensioner bolt (aftermarket) or plunger (stock) pushes on a slider rail located inside the channel which the chain rides, all bathed in oil to minimize friction and wear. If you can get your head in there to see down the channel where the chain goes you can probably see it with a flashlight. I hope that answers your question.

Once you have the cams aligned and all that, you need to do a leakdown test to make sure you didn't bend a valve...or worse.

 

im saying the stock plunger doesnt have no movement, how would it tension in the first place

 

The bolt on the top of a stock tensioner is a plug..... all it does is come out.....

Now if you remove the bolt you can insert a tool to back the tensioner off and lock it in place before removing it.

If you just pulled it out, it is now completely extended and yes it won't move, unless you take a tool (a thin screwdriver can work ) and wind the tensioner back in.

 

Yep! What he said! ^^^

 

the thing is, the plunger is pulled in and it wont come back out. ive seen pics of tensioners and they are way longer. Its like the plunger got pushed in and doesnt want to come out. Is this what happens when it goes bad? Also is there a thread on "how to " do the leakdown test?

 

If from the sound of it your CCT has failed you'll need to replace them (ideally with manual CCTs) reset the cam chain and and valve timing to spec, before you can run a compression test/check the valve clearances for valve damage.

Leak down testing

http://www.dansmc.com/leakdown.htm

 

As suggested, the CCt sounds like it is done.
Spend some cash on TWO new ones
Search
$59 each

Or a set of manual CCT's

The leakdown test, is, well, if you have to ask, you likely do not own the tester needed.

Same with the compression test


If your willing to buy the tools, have the air compressor, the procedure is not terribly hard to do.

I wrote an article on the differences and use for each,
Leak down Test and Compression Test - DRZ400 FAQ - ThumperTalk
But not a how too.. most folks I guess that have the equipment, have the how too part down.

but Im willing to write an article specific to the VTR, if it'll be of use.