Got defeated this weekend

[petejw]

I bent 4 inlet valves the first time i adj the cam, when i first got the bike, wat i did tho was to over tighten the lock nut which made the bolt lose its tension on the adj, i was able to ride it 4 2 hrs bring her home and let it cool, when i went to restart it a few hrs later, the bike backfired thru the carbies b4 the sound of clunking cld be heard, thats when the chain slipped causing the bent valves. I hope you guys get to figure out the problem, i know theres nothing more frustrating.

JAT I adj my cam chain yesterday per instructions with the valve cover off, the spring in the tensioner didnt seem to be strong enuff to make the chain tort. I ended up removing the plug from the back of the tensioner and with a rod pushed on the plunger, this made a significant difference, maybe something else to look at.

[wa407mpp]

Sorry to be so late getting back on here with my reply, but a busy work schedule and slow Internet seem to have conspired against me. The main difference between adjusting the cam chain and installing the cam chain adjuster is that when adjusting the cam chain, the chain is held captive by the adjuster, and all you are doing is allowing the adjuster to move enough to take up the extra slack in the chain. However installing the adjuster is a lot more involved, because when you remove the adjuster you release the pressure on the cam chain and the slack is free to slip to the lowest point in it's loop, which is under the crank sprocket, where it hangs in a loop until you reinstall the adjuster. When you install the adjuster you have to recapture that whole loop or it will travel around it's normal route and cause engine damage as it equalizes it's self, That's why it is important to not mix the two procedures and the main difference is that when adjusting the cam chain the engine is completely assembled except for the ignition cover and when you install the adjuster you need to have the cam cover removed so you can not only see the chain and check the timing marks, but also make sure you remove all the slack. You do this by pre adjusting the adjuster about half way out and finger tightening the adjusting bolt, then grasping the chain between you thumb and forefinger and gently pull the chain up until the slack is at the top next to the front cam sprocket, making sure it's on the crank sprocket, then while holding it there, you slide the adjuster into place, releasing enough chain as necessary to allow the adjuster to be bolted in place and in contact with or at least aligned with the chain, then slowly release the pressure on the adjuster bolt allowing it to adjust the chain the rest of the way, keeping your fingers out of the way as you do. Now when reading trbig's first post there was no mention of bohn removing the cam cover and in John's post he said trbig removed the cover to check the timing, maybe it was removed by bohn, maybe it wasn't, but until corrected I'm going on the assumption that it was not removed. When you install the adjuster without removing the cam cover there is no guarantee you will get all the slack out of the chain or the chain on the bottom sprocket and here I agree with trbig ,but for a different reason, because of the small size of the crank sprocket and the chain is a short link chain, which tend to bunch, if you let the adjuster snap into position from full out you could cause the chain to try to snap into position so fast as to allow the loose chain loop hanging under the crank sprocket to grab a sprocket tooth on the on it's way up and leave the some of the slack trapped on the sprocket until it is turned and also giving the impression that the adjuster has removed all of the slack. It says in my book,that it only takes an 1/8th of a turn on the cams,to cause damage to the valves from contacting the pistons, so it stands to reason that a few links of slack suddenly appearing in the cam chain could cause this to happen. As I previously stated, right or wrong I came to this conclusion from the experience and training I have gathered over the years and from the information in this post, and in no way am I judging any one's mechanical ability or expertize. From reading the post on this site it appears adjusting the cam chain is causing a lot of problems and I think mostly it is because the repair manuals leave a lot of general information out, because they assume if you are doing you own maintenance you know it already. One very important bit they skipped over is when you adjust the cam chain you need to rotate the crank enough times,"at least 2 to 4 complete revolutions", to move all the slack to the front part of the chain, I know that I already said the slack travels around the chain, but not at the slow speed of hand turning the crank, only at running speed, if you want to test this theory pedal a single speed bicycle both fast and slow with the rear wheel off the ground and the chain a little slack. I know it seems like extra work, but it's also important to remove the spark plugs, it not only makes it easier to turn the crank, it also makes it possible, after making the adjustment, to feel, if the pistons contact the valves which could be mistaken for compression resistance with the plugs in place. This is my theory of what happened and how to prevent it. If you don't agree feel free to attack it, but don't attack me personally.

[xschop]

Enigma

Not sure if this could be the phenomenon....
Last weekend I put a water pump on my Civic, removed timing belt after setting the obove head cam and crank according to book at TDC for #1. After doing so, when I went to loosen the timing belt tensioner, I noticed that the pressure in the Cylinder had turned the crank below a complete tooth off. I was lucky I saw this and not assume that all the marks were aligned when I put it back together....strange, but did happen.....Chop

[wa407mpp]

After rereading the posts, I discovered I misquoted, it was later in trbig's first post that removing the cam cover is mentioned, not in John's post.

[Crazcnuk]

That makes sense as far as what I experienced. I never thought about ALL the slack being gravitationaly impaired and falling down.

This would explain why it seemed to set properlly, yet still had slack after I wrecked the top end.

[thewiz]

Powerfully important ...

information and proceedure details there, WA .... and thank you very much for taking the time to paint such an excellent word picture of what's actually happening inside there.

I'd venture to say that many or even most of us have removed a cam chain tensioner at some point ... some of us multiple times without ever taking off the cam cover to peer down into the block and observe what's going on (unless something goes wrong)... speaking for myself in particular, I think that it's only by lots of luck and the smallest bit of instinct that I personally have not bent a bunch of valves in the process of so doing.

I have one to replace on my G very soon and you can bet that I'm definately gonna take EXTRA care when I do.

[SFerinTEXAS]

Happened to me about 2 months ago. Took the tensioner off to replace the gasket. Reviewed manual first and thought all was well till I started up and heard that unmistakable (now) sound of a loose chain in the valve cover. Thinking I had done the tensioner replacement correctly it was not my first guess . Then when it died and would not restart I came in and searched the site for every post ever written on the subject. yada yada etc. Luckily only jumped 1 tooth and did not bend any valves. Needless to say now removing the tensioner is a high red alert procedure . I realize this reply does not help with the original purpose of the thread but all the replies surely will be a big heads up to some others I hope.

[Dan Hodges]

Bent Valves

Has anyone heard from Frazier relative his mechanical problems and did he ever conclude what caused said problems?

[XJOK2PLAY]

Dan,

I just spoke w/ Cody, it's back on the road. Bent intakes... just didn't get the chain tight for whatever reason the first time... I'm sure Bohn can tell the whole story better. Headin' out to Colo. w/ him Thursday am, as well as Cody, Tod, Rod, and meeting up w/ Miles. Said he'll be takin' the 11.
Bob

[Dan Hodges]

That Dang Chain

I just spoke w/ Cody, it's back on the road. Bent intakes... just didn't get the chain tight for whatever reason the first time... I'm sure Bohn can tell the whole story better. Headin' out to Colo. w/ him Thursday am, as well as Cody, Tod, Rod, and meeting up w/ Miles. Said he'll be takin' the 11.
Bob

Very good, all's well that ends well. There might be only 50 ways to leave your lover, but there's at least 1100 ways to hatch an Eleven. Oh yes, while on a Rocky Mountain High, don't try to make a Ninja out of an XS11, way too dangerous. Thanks for the update.

[trbig]

don't try to make a Ninja out of an XS11, way too dangerous.

It'll be OK since I have an XJ11 Ninja!!

I'm not as worried about the hairpins (Actually looking REALLY forward to those..) as I am the carbs operating worth a crap above 14k feet where we'll be at times.

Speaking of.. I think I better go grab another set of plugs. I'm running a bit lean right now which may help up there.. but it wouldn't hurt to have a set in case of fouling.


Tod

[thewiz]

Had my first Eleven ...

in those mountains. Would love to ride there again one day. Have a safe trip, Tod and the others.

[Dan Hodges]

Rocky Mountain High

It'll be OK since I have an XJ11 Ninja!!

I'm not as worried about the hairpins (Actually looking REALLY forward to those..) as I am the carbs operating worth a crap above 14k feet where we'll be at times.

Speaking of.. I think I better go grab another set of plugs. I'm running a bit lean right now which may help up there.. but it wouldn't hurt to have a set in case of fouling.


Tod

I've been to the high country several times and each time I changed my carb jets before I left because being dead nut on for 400 feet at St. Louis makes for a sick runner at 10,000 feet.......been there and done that.

[trbig]

Well.. the carbs worked just fine. The bike was quite a bit slower to respond at that altitude, but with it running a little lean here, it worked out well up there. When I was running really hard into some of the twisties and Cody on his Concourse trying to catch me, (Yes you read that right.. the XJ Ninja was tearing it up!.. lol) he was close enough to see my rear tire and said he could see smoke coming off of it when I was cornering really hard. The outside edge looks like a roughed up eraser now... not a chicken strip (Little rubber tabs on the outside edge of the tire) left to be seen!

I'll have a ride report soon with some pics..

Tod

[Dan Hodges]

Smoking Something

Well.. the carbs worked just fine. The bike was quite a bit slower to respond at that altitude, but with it running a little lean here, it worked out well up there. When I was running really hard into some of the twisties and Cody on his Concourse trying to catch me, (Yes you read that right.. the XJ Ninja was tearing it up!.. lol) he was close enough to see my rear tire and said he could see smoke coming off of it when I was cornering really hard. The outside edge looks like a roughed up eraser now... not a chicken strip (Little rubber tabs on the outside edge of the tire) left to be seen!

I'll have a ride report soon with some pics..

Tod

Back in the disco days, 81 Specials came through with 110 mains straight across, 185 pilot air jets & 42.5 pilot jets for us normal folks however Denver Specials got # 200 air pilot jets, same pilots and 107.5-105 mains. This made for a crisp running combination for that area but would have been lean at less than 2,000 feet. California Specials also fetched the #200 pilot air jets even though the shop manual list # 185 PAJ's for all. I rode my 81 Special to Denver, Colorado in the early 80's when it was box stock and it actually ran okay around Denver but as I went north the altitude increased dramatically and around Estes Park it was around 12,000 feet and at that altitude it was running really fat. I went up to the park on the west side and came back to Denver on the east side and once I drooped back down to the 6,000 foot level it was okay again even though it was still funky at idle and off idle and on starting. I took the plugs out that night and they were very sooty. I put them back in and used them on my trip back to St. Louis and by the time I got home they were a funky tan color, I still have those plugs. In 90 I took the Special west again only this time I had 190 APJ's and 105 mains and it ran perfect in the mountains. That ride coming down the east side of Rocky Mountain National Park to Granby is really cool as some places of the road is like a snake. On all of my XS trips to Colorado I left home with new Dunlops and by the time I got back to St. Louis the back tire was wore completely out. In 85 I trailered my then new 900 Ninja along with my friends Honda 1100-F to Denver for some sport riding. Both bikes were sporting Kerker pipes and St. Louis jetting and both were gagging up in the mountains if you had the throttle wide open. My Kaw was fine until you reached about 6500 rpm after which it started acting like you pulled the choke out and I learned years later that this was the point where the slides were pulled up in the fully raised position causing it to go fat at altitude. The little red 900 administered a severe ass whoupin to the big blue 1100-F Honda that day in the mountains however later that fall the little red Ninja suffered engine damage of Biblical proportions due in part to cam lobe failure and it's no longer with us. The big blue Honda is still out in Washington, Mo. in my friends garage with a somewhat stoked 1123 motor and at this point it's still a little quicker than my stoked Eleven but I'm getting close and will close the door on him with my next upgrade. Sounds like you had a good time, are you sure ole Cody on that silver bullet wasn't just stroking along on a Rocky Mountain High site seeing as that C-14 of his is pretty stout and even though he may be getting a bit long in the tooth he is still a pretty capable "pilot".