Recent cam tensioner change, now I have a problem

satanzhand · 11-27-2008, 12:58 AM

Hi all, early this year the spring broke on the front cam chain tensioner of my 97 VTR 1000 at 40,000km. Luckly, there's no damage (I believe). I now have replaced the standard spring loaded tensioners with ridged APE cam chain tensioners.

So the problem I have ( which is probably of my own doing ), is, in my hast to get riding again I did not TDC the front cylinder (or the rear for that matter). So now, the bike will some what reluctantly start but has a very slight back firer through the exhaust then the carb. My guess is that maybe the chain jumped a tooth or something when the orginal cam tensioner broke and I never noticed it because I did not TDC the front cylinder or maybe the cam tensioners are to tight or its something random I have not accounted for.

So does anyone have a check list or something i could go through before I start pulling everything apart again.

Many thanks

denzee · 11-28-2008, 8:49 AM

How did you know your tensioner was broke in the beginning and did it sound the same as it does now?? Was there a device holding back the spring on the tensioners that was to be released once installed? I think it would tension the chain properly even if it wasn't at TDC on a power stroke.

nedro · 11-28-2008, 11:28 AM

Wish I could help, but it looks like you'll be doing some engine work to sort things out.

satanzhand · 11-28-2008, 6:06 PM

Yep your right I have had to strip the bike down again. The timing was out a bit on the front cylinder. But I think I sorted it last night. I just have to put it back together and give it a test start to confirm I have got it right.

To answer the other reply.

I heard the snap of the tensioner spring. I backed off hard on the throttle at a corner at the bottom of a steep hill. I think the back pressure put stress on the cam chain which caused it. Anyways, the snap was followed by loud cam chain slapping and tears.

The APE cct's seem to be the ticket to repair it over the stock ones.

satanzhand · 11-29-2008, 12:24 AM

Dup!, I think i've set the front cylinder 180 d out........damn... it wont run.

I am going to be an expert at this by the end.

satanzhand · 11-29-2008, 3:13 AM

I have reset the cams correctly I believe this time. But now it wont start...hmm although I test ran it with the rocker cover off and it did run sweet. But of course once its all back together no start......bugger...

I'm hoping its just flooded or something!

Any ideas anyone... this is starting to become a mission.

macca9540 · 11-29-2008, 3:25 AM

Mate, I can't help with your drama's as i don't know how to time a VTR 1000, but i would be use extreme care with the timing as you don't want to valves to start kissing pistons. I personally would get the timing set by someone in the know. Just my opinion and good luck.

satanzhand · 11-29-2008, 7:41 PM

Thanks for the advise.

Luckly I know enough not to do that, Just unsure on the settings for V-twin. cars and 2 strokes are where my experience is so this is a little new to me.

Plus I a student so I am totally broke!

nicktuck · 12-02-2008, 6:36 PM

Buy a Manual and check the timing, can be very expensive if you get it out of timing, I had the cam tensioner spring brake and ended up siezeingat the lights luckily, new pistons, few valves,etc.

satanzhand · 12-02-2008, 7:22 PM

I have the diagrams of the bike and the service manual. Between the two it has not been that clear on the setting for both ends when they are complete outta wack (which didnt happen while riding, but during the what the hell has happened here period of diagnostics).

Anyways...I've sorted it now, and am just giving an oil change just incase any bits have gotten into the oil.

Just as a hint to anyone else setting the cams/valves for both cylinders the two sides run about 180 degrees behind or in front of each other so you set the rear nobes up and in / \ and the markings fi out fe out and parrallel to the top of the headcasing (or cylinder head as it says in the manual, although you cant see the piston or the head on the cylinder so i'm not really sure what good saying that is) and then rotate the crank as per the manual to FT and line up the front cam nobes up and out \ / and the cog markings fe out fi out parrallel etc etc and then .... make sure you've secured the cam chain etc give the crank and few test turns to make sure nothing will smash off... It also pays to check everything is working in the right sequence as well...and your away.

Also, I learned the lesson the hard way from car engines

. Change the oil and filter before you ride the bike again! Why? you ask...because if one little bit of cct gets to the bearings or worse oil pump you are in big trouble.... example. the oil pump gets a little damaged..oil pressure drops ..wear increases and the engine goes bang or should I say knock knock

satanzhand · 12-08-2008, 5:22 PM

I am all finished now I have a few tips that might be useful.

1) Ape cct are great.
2) No matter what check the cam timing on both cylinders
3) adjust the tension on the Ape cct as recommended then loosen off another 1/4-1/3 inch turn at the bolt

4) Change the oil and filter just in case any bits got into it.
5) check that the engine moves freely before you try to turn in over with the starter motor.