This is probably going to be about 3 posts in one. My apologies. For those that can stay with me, I appreciate the feedback.
Had problems in the fall with starting while it was cold out. Forums suggested adjusting the valves. This spring, a plan to pull the oil pan to fix a leaking plug turned into rebuilding half the engine. I have just completed:
-replaced the rings
-honed the cylinders
-lapped the valves
-adjusted the valve clearance
-replaced all gaskets
-spark plug caps are new
-spark plugs are newish (<500 miles, replaced in fall)
Last night went to start it up, and to my amazement, it actually started! (This is the first time I've done anything like this with an engine. Thanks goes out to everyone that helped with replying to my previous posts!) However, after all this work, the thing still isn't running right. It won't idle, even after warmed up, without the choke on. More info:
-checked compression, got 175-180 psi dry in each cylinder with full throttle on. wet compression was insanely high, over 250. (Random question, why does the compression go up with full throttle? Initially I cranked the bike with no throtlle, and was getting 60-90. With full throttle, it always went right up to 180. I don't understand this.)
-the bike does respond to the throttle, and will rev up to 5,000+ rpm with no problem using the throttle.
-I attempted to adjust the idle screw (behind the carbs, below the airbox, facing rear) with no effect (side question: is IN higher/faster idle, or is OUT higher/faster?)
-just for kicks, I removed the air filter while the bike was running, and that had no effect whatsoever. Same with the cover on and I plug in the air inlet hole.
-the bike starts with the choke on and runs around 2000 rpm. as it warms up it gets faster and faster. i can keep turning the idle down to a point, but once it's warmed up, the choke still needs to be about 1/3 on in order for the bike to stay running.
-the PO *said* that he'd recently had the carbs worked on when I bought the bike last summer (yeah, right)
-I started the bike on a warm day over the winter *before* any engine work, and it was exhibiting symptoms similar to what it has now.
From doing research on the forums, it seems that this could be caused by any one (or combination) of four things (that I found, anyway):
1. clogged carbs
2. bad/clogged petcock
3. Bad gaskets/seals/rubber on the boots between the carbs and the engine
4. leaks from the airbox.
The seals on the fuel boots seem ok. The rubber isn't cracked, and I tried spraying WD40 on them while the bike was running, with no change. Given that the bike revs to high rpm ok, I'm going to guess it's not starved for gas, thus the petcock is probably ok(?). And, knowing my luck, between any 2 problems I'm going to have the harder one, so it's probably the carbs.
There seems to be some disagreement as to whether to just clean the parts and change the o-rings, or buy a whole rebuild kit:
I guess I'm going to try the o-rings first, then order rebuild kits if anything seems to look suspicious. Does this sound reasonable?
Given that I know nothing about carbs (I knew nothing about rebuilding an engine a month ago) I'm sure I'll find the GS carb cleaning guide very helpful:
I assume that after a rebuild/clean of the carbs, I'll need to synch them? (Again, don't understand how to do this yet, but I have the manual.) Should I get an actual manometer:
or just make one myself:
http://www.vfrdiscussion.com/forum/l...hp/t16200.html ?
Is there anything that I can to do harm the bike by using a homemade manometer? How often (time/miles) do you really need to balance the carbs?
But before I get into this, am I on the right track? Is there anything that I could be missing that could be causing this? Anything else I should check or look at? Anything else this could be? Anything else I could to in order to narrow down the problem? Any other info you need in order to better advise me?
If I need to take the bike someplace, is it going to *hurt* anything to leave the choke on while riding it?
Thank you everyone for your advice. (Last side note: I showed one of my friends who's a scooter-head to a previous post on this forum. He said "Gee, your suzuki guys are friendly. When anyone posts a newbie question to the scoot forums, they often get flamed big-time." Just so you know...credit where due...)
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