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Discussion Starter #1
hi everyone,

First let me tell you this looks like a great site. Very well done indeed!

I just bought a 2001 SV650S with 3k miles on it for my wife. Bike is fully stock. The bike was used very little, and sat for about 4 months before I bought it. The dust that was on it confirms this. It was running rough, but I thought that a simple tuneup and some carb cleaner should take care of the problem.

I have already done the following:

- oil/filter change
- Coolant flush
- Changed spark plugs (what a pain to simply get to the front one.) BTW, neither needed changing, but changed them anyway.
- emptied gas tank, let the bike run with tank off until it used all gas in carbs, and put in fresh gas with carb cleaner in it. Sprayed the carb assembly with carb/choke cleaner, and sprayed some down its throat while running.

- Air filter looked good, so I didn't change it.


After going through a gallon of fresh gas mixed with Gumout carb cleaner, it seems like it is running much better. Full throttle sees a little hesitation, but not too bad at all. Only steady cruise at around 4-6k rpm sees constant (but little) hesitation. There is also a lag, a delay if you will, between when the throttle is opened/closed, and the time the engine responds.

I personally think that carbs needs to be pulled out and cleaned out, and may be a rejetting while at it. I have never done any carb work, but don't mind doing it myself to learn as well. (I do all maintenane myself, including valve adjustments, etc.)

Before doing this, however, I thought I might as well get some info from this board, see if anyone has any other suggestions.

I appreciate the help.
 

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Welcome to the site and the wonderful world of SV ownership...



On the 1st gen SV's ('99-'02), there is a noticeable flat spot in power delivery at around 4500 rpm, even under hard acceleration. Elsewhere, the power band should be butter smooth and linear. You have already begun to attack what is likely bad fuel and/or buildup in the carbs, I guess I would run a couple full tanks of fresh fuel through it, being sure to get on it hard at least once (seriously, this will help clean it out a little). You may want to be the one to spank the throttle if your wife is the primary rider and it's her first bike.

If after a couple tanks the hesitation is still really bad or somewhere other than the previously mentioned normal 4500 rpm stutter, then you may be looking at more intensive trouble shooting involving the carbs/float bowls.


HTH


p.s. Is the air cleaner clean?
 

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Lubricate the throttle cables and throttle linkage. That might help. Lubricate the clutch cable also. It's been sitting awhile.
 
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Discussion Starter #4
For the stock bike with stock pipes:

Pull the carb and replace the idle jets with next size up (can't remember what they are anymore but I think 17.5s. Turn them out 2 1/4 turn each.

Then, pull the needles and put one 3mm shim under each.

The stock idle jets of 15 are too small. The main jet is OK for stock pipes.

Can clean everything while in. Remember to pull the carbs completely away from the intakes before drilling out the idle (fuel screws) screw brass caps.
 
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Discussion Starter #5
Thanks everyone... great advice all around.


Well, after reading about this "TRE" crap, this morning I went ahead and removed the two corresponding wires from the main connector under the rear seat.

For those who may do a search and come to this post in future, the two wires that I pulled out are: top row, wires no. 3 and 4 from left: red/yellow, and green-blue. (Left when standing by the driver seat and looking towards the back of the bike.)

Anyhow, after doing the TRE mod, almost all of the hesitation that I was talking about has disappeared. After owning many different bikes (such as F4i, Superhawk, R1, Katana, Nighthawk, Magna, Ninja 250, etc.) I can't believe that Suzuki engineers would be this cruel to the poor SV650. I have never seen a bike intentionally misbehave in two consecutive gears. I was associating all of this with carb issues.

Once again, thanks everyone for your suggestions. I will definitely do a rejetting later on, as the bike still seems to run a bit too lean.
 

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faz said:
Well, after reading about this "TRE" crap, this morning I went ahead and removed the two corresponding wires from the main connector under the rear seat.

For those who may do a search and come to this post in future, the two wires that I pulled out are: top row, wires no. 3 and 4 from left: red/yellow,  and green-blue.  (Left when standing by the driver seat and looking towards the back of the bike.)

Anyhow, after doing the TRE mod, almost all of the hesitation that I was talking about has disappeared.  After owning many different bikes (such as F4i, Superhawk, R1, Katana, Nighthawk, Magna, Ninja 250, etc.) I can't believe that Suzuki engineers would be this cruel to the poor SV650.  I have never seen a bike intentionally misbehave in two consecutive gears.  I was associating all of this with carb issues.
Where is the procedure for TRE mod listed? ???
 
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Discussion Starter #9
algreen said:
Where is the procedure for TRE mod listed? ???
I am new to this site myself, so I did a search on TRE MOD and found many posts. One had links to various posts and sites that show how it is done.

But I basically said the procedure in my post :) Just remove the rear seat, unplug the connector with many wires on it, push out (from inside) the two that I explained, put some electrical tape around the ones you pushed out, and put the connector back in.
 
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Discussion Starter #10
Just an update: after a few days or riding it, it has not gotten completely smooth yet. Noticeably, around 5.5-6k rpm, at constant throttle, there is constant hickups.

1/2 throttle and full throttle are all normal. Only the 1/4 or less throttle application is jittery. I am suspecting: out of synch carbs, or pilot jet starvation. I have never taken carbs apart, but I do have a haynes manual and it has it explained pretty well. I will probably try and find some local svrider in san jose area to watch over my shoulder. (anyone on this board in san jose??)

Any thoughts on what I should watch out for, or do before pulling the carbs out? Does anyone know if simply shimming the needles is going to fix the problem or not? I am assuming for raising the needle I don't need to remove the carbs.
 
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Discussion Starter #12
I just wanted to drop a line here and thank everyone who contributed to this thread.

Just a couple of hours ago I finished putting the bike back together after doing a complete carb overhaul/cleaning. One of the float bowls had dirt in it, and even though the jets were not that dirty, they could use a cleaning. The bike is totally stock, with stock air filter and exhaust.

I went ahead and changed the pilot jets to 17.5 (from stock 15), air/fuel mix. to 2 1/2 turns out, and moved the washer from top of the needle to underneath it. After putting the bike together tonight, I went for a quick ride, and all I can say is "wow". Creamy smooth, and definitely more power all around. I also changed the screws at the bottom of the carbs with Allen type, for next rejetting (make it easier to take them off.) I also added a 1.75' vacuum tubing to the front carb's vaccum inlet, routed it to where the rear carb's vacuum hose is (right next to gas tank petcock), plugged the end, and left it there to make the future carb synch's a piece of cake.

Thanks to everyone who made suggestions and helped me with this task. You guys are great!
 
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