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Discussion Starter · #1 ·
After over a year of intermittent dying at stoplights, bad hesitation on acceleration and three trips to the dealer for 24K service and a $250 fuel filter change, I decided to take the bull by the horns. Tupperware came off (1st time), airbox and TB's came off with a little help from my friends here (previous thread), and now I am deeper into this engine than I have ever been. I have in hand four new TB connector boots, eight injector o-rings and a new crankcase breather tube, possible the most expensive rubber tube ever made. On first inspection of the TB's after lifting the throttle valve rail, I noticed heavy oil wetness on #2 and #3 throttle bodies. After removing the breather hose and cleaning, there didn't seem to be any holes or cracks. I've stopped for the evening, but will be back tomorrow afternoon. Anyone with suspicions or thoughts would be most appreciated! I really hope to get her back in tiptop running shape.
Nick
 

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First thought.. congrats on having the motivation to get in there.

Regarding your situation.. I'm guessing the hose, fittings or o-rings were leaking.. Hard to debug from here.

Since you are replacing the parts, I would just ensure everything goes together smoothly... then "enjoy".
 

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Dick,

not that I could give any hints on the reason for your symptoms (other than you have figured out yourself already) but when you are putting everything back together, please make double sure the hose clamps (for the TB's) go in correctly. Their positioning needs to be just right so that they don't interfere with the throttle linkage.

If you wonder how I know, here is more about it:

http://picasaweb.google.fi/pozoizquierdo/AVERYEDUCATIVESERVICEVISIT#


Regards
 

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Discussion Starter · #4 ·
Thanks for the replies guys.
I read the "Very educative first visit" with much enthusiasm, as his TB's look very much like mine, with the center pair of TB's most affected. A pro mechanic friend looked at the TB rail last night and commented about the design of the breather tube itself- that the "flow of gasses may be heavier in the center (#2 & 3), thus causing an imbalance in the function of the system in that area", and suggested separate hoses from each TB to a block, and then a single hose to the crankcase. It seemed to make sense to me and I may try it. In any case, I'm aware of the hose clamp situation, so thanks for that! BTW, does one have to disengage the throttle cables? That seems to be a project all by itself.
Best,
Nick
 

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I'm no mechanic... but it does make sense that the "shorter" distance to 2/3 would have more flow.

Ideally this would "split" from the single outlet to a "manifold" that then distributes. There is enough space to do that. With some Rube Goldberg motivation, I bet a few minutes at your local parts distribution house (not AutoZone) you'd be able to assemble something that would do that from brass components.
 

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Discussion Starter · #6 ·
...not to mention no need for a $70 rubber hose...
 

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Gentlemen About two years ago I looked at mine and come to the same conclusion as your mechanic. I went to buy the hose, Not wanting to take the time to machine something. I would much rather ride. The Dealer said it would be 10 days to get the hose in. Then came the price.I AM NOT PAYING 70.00 dollars for a 6" hose. I took a few measurements and about 30 minutes on the lathe I had a nice manifold turned out. Cut a few pieces of tubing and a couple minutes tig welding then let it cool and I have a manifold that will never need to be replaced and as far as the hoses go it's only about two dollars for all the hoses at the highest priced place to replace them. I have gotten tired of the exorbitant prices that the dealer keeps quoting me.
 

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Discussion Starter · #8 ·
Very interesting! Did you snap any photos perchance?
 

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Nick,


I am not trying to burst your bubble but EVERY LT I have taken apart, running perfect or not, the TBs have looked exactly like yours. Look deeper for the cause of your problem like a vacuum leak. So check over the lines from the cannister if it is still attached. Actually the cannister line goes to the vent valve and is manifolded out from there, so check those very carefully. Heck if you have done the cannisterectomy just plug all the vacuum line ports.
 

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Discussion Starter · #10 ·
Thanks, John. That's good information. Tells me that this is a common failure, and I will check the vaccuum lines carefully. The cannister has been removed and lines plugged, but it still ran like crap. I just got the injectors out this evening. BTW, my bike is a 2004, and I just rolled 30k. No reason that the middle ports should be so oil-soaked. Injectors also. I will be cleaning and re-fitting in the coming days. Thanks to all.
 

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ICXC said:
Thanks, John. That's good information. Tells me that this is a common failure, and I will check the vaccuum lines carefully. The cannister has been removed and lines plugged, but it still ran like crap. I just got the injectors out this evening. BTW, my bike is a 2004, and I just rolled 30k. No reason that the middle ports should be so oil-soaked. Injectors also. I will be cleaning and re-fitting in the coming days. Thanks to all.

I've got my LT pulled down at the moment for a new clutch (and a major service at the same time), it's the same vintage as yours with a few less miles. It's exactly the same as yours, the middle ports are covered in oil.

So..... where does it come from???
 

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Discussion Starter · #12 ·
I'm putting my money on the issue with the breather (see posts #4 and 5 above). Stated another way, the problem may reside in the fact that the design of the breather "plenum" causes crankcase gasses to hit that area first, and with more pressure and heat than the outer two ports. (The gasses flow INTO the TB's from the crankcase). I'm going to put my pea-brain into designing a different type of breather tube to eliminate this as a possible cause. Right now I'm focusing on the type of hoses which would be appropriate to connect to the TB outlets and how to route them into the one which connects to the crankcase, maybe fuel injection hose.
 

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Discussion Starter · #13 ·
Daz-
Are you doing the clutch yourself?
 
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