| Author | Message | ||
     Roderick |
Noticed something on my '98 S1 before leaving work today: There is about 1 mm of daylight between the front cylinder head and the front mount. Is this normal? If not, is the front iso bad? Going bad that it will cause the front cylinder head to touch the mount soon? May be I missed it, but I do not recall seeing anything in the service manual about this. Roderick | ||
| 01x1buell |
well the mount is bolted to the head, so it should not move, on my x1 it is close as well, even if the iso is bad the gap will not vary due to it being bolted to the head. if it is super close maybe broken bolts on the mount . | ||
| Greg_cifu |
If you just described that properly, no, there should not be ANY gap at all between the aluminum front mount and the cylinder head. You should not ride the bike until you sort that out. You either have a loose bolt that's about to break or it already failed and your engine is about to drop. | ||
| Roderick |
I guess my description was not good.  The photo does not show, but that tiny gap is where the arrow is pointing. It is not actually in contact. It just look that way from this angle. I do not think the cylinder head should be touching that ridge on the mount, correct? | ||
| Steveford |
What does that front isolator look like? | ||
| Beardo |
That's normal. The only point of contact is where the bolts are. That's actually a strengthening rib cast into the mount. I just went down to look at mine to see what you were asking about. | ||
| Roderick |
The isolator looks fine, for 15k mileage. From just a few ft away, it looks like the cylinder head was in physical contact with the mount. I had to crouch down and get real close to see that tiny bit of daylight. I do not know if this little gap is normal or should there be more, like at least an inch or so. It just look awfully close between the cylinder head and the mount considering engine vibrations and running on the roads. | ||
| Kalali |
I just looked at my X1 and that gap is just about 1/8". Technically that gap should be fixed and not change if everything is solidly bolted. | ||
| Steveford |
I just took a look at my S1 and it's pretty tight but the rocker cover doesn't hit the front isolator mount. It looks like you're worrying about nothing. | ||
| Roderick |
Thnx much, gents. Good to know. But I will keep periodic checks on it just in case... | ||
| Ratbuell |
That mount is bolted directly to your head; they are, effectively, a single piece and will not move in relation to each other, they will only move together. That 1mm of daylight will be 1mm of daylight no matter how much the head moves...because the mount moves with it. IF you start seeing the mount move in relation to the head, get a new set of bolts immediately because that is a sign of bolt stretch/fatigue, which leads to broken bolts. | ||
| Beardo |
Rat, that brings up a question. Is there a known life span to these bolts? And what should they be replaced with? Meaning, does a particular company make better bolts than another? I assume grade 8? | ||
| Ratbuell |
http://www.americansportbike.com/shoponline/ccp0-p rodshow/A17049-B.html Grade 9. "Lifespan" would be measured in wheelies, not so much miles or years  | ||
| Beardo |
Just out of curiosity, are the original bolts grade 9 as well? | ||
| Jramsey |
http://www.allensfasteners.com/search_results.asp? txtsearchParamCat=73 Scroll down to 7/16" x 14 x 2-3/4", $1.55 | ||
| Ratbuell |
The kit Al sells IS the original bolt kit. | ||
| Bluzm2 |
I believe the mounting bolts are a one time use item. They are designed to stretch when installed. Much like current automotive head bolts they won't do that a second time.. | ||
| Beardo |
OK, that makes sense. One and done. Clears things up. The information is much appreciated. |
