Suzuki GSX-R Motorcycle Forums Gixxer.com banner

GSX-R 600 Info needed Track - Stock

2K views 27 replies 11 participants last post by  poisonouschimp 
#1 ·
I picked up a 2001 gsxr 600 with 17k miles for 1600 bucks for my gf as a starter bike. The previous owners were a couple who took their bikes to the track and have done a lot of "track" mods to the bike.

Just a quick overview of the mods: GP shifter, power commander, fiberglass race body, headlight removal and pen light attached, different front end with upgraded suspension and bars, gsxr 1000 brakes, security pins all over.

One of my main concerns is that at low rpm ~3k at constant throttle you can feel air kick out of the air stack runners if you have the air box off. As a result of the popping at low speeds for a new rider it makes it a little difficult to ride. I have been riding for 5 years now and just use clutch control to smooth it out, but that takes time to learn to do. At higher speeds and rpm past ~5k the bike smoothes out and rides great. I took it up to 11k rpm and 100mph and there didn't seem to be any odd issues. There did seem to be a harsh on/off throttle kick when lane splitting ~ 7k rpm.

What I have noticed from inspecting the bike thus far is the REED valves have been removed and they have been welded shut. The Vacuum lines on the runners have been rerouted and one port has been capped off. The air box itself has many ports capped off. The secondary butterfly valves have been removed from the air inlet runners. When starting the bike up it requires a throttle blip to turn over as well as the throttle blip'd a few times to hold the idle and the idle is set around 800-1k.

When speaking to the previous owner he keeps saying that the mods were intentionally done as part of race prep for the bike. He says that the bike in its current state is meant to be run 7k and higher rpm and that low end burps are normal for the mods done. I am wanting to just confirm this since I have never had a "track/race" bike before. I ride a 2003 gsxr - 1000 that only has a Yoshi and power commander with the rest of the bike being totally stock. I am also an auto mechanic so symptoms of kicking air backwards in the system doesn't make a ton of sense to me as being a normal operating condition.

If anyone can link me literature on these mods or just inform me places to go to get the info that would be great. I am just really not sure what to look up on this since I never really deal in performance mods for motorcycles.
 
See less See more
#3 ·
What is a gp shifter?

Your idle appears to be a little low. Cold idle should be ~1700, and warm idle ~1250.

The PAIR valve mod sounds correct but with out pics it's hard to say.

I guess I'm not understanding what you are really looking for from us? Nothing sounds too out of whack

+1 on what Maniac said.
 
#13 ·
I was thinking of adjusting the idle screws up on the bike for the cold starts as my first step. I just wanted to make sure the PAIR mod was a normal mod that people do on here and not just some guys "secret mod" that he claims makes things way better...like a Cold air intake sitting on top of the exhaust manifold sucking in all the hot air lol.

What I am hoping to get from you guys on the site is just an overview of the current state of the bike, if I can convert it back to stock easily with the current set up, any links to the mods the bike looks like it has since I have no idea what to search for (like names of the mods). I don't know any performance shops near me who would just check out the bike and I don't follow any bike clubs. I basically just commute around on my 03 gsxr 1000 when I feel like it and like to take it lane splitting when the traffic is really heavy, weather permitting. I don't really canyon carve or track the bike...I prefer sports cars for those things with full cages. I hear too many stories of a biker thinking a canyon is motoGP and hitting a dirt patch and either destroy the bike or themselves. I am happy enjoying being able to park where I want, lane splitting, the occasional straight line freeway race vs a Ferrari lol.

As far as the GP shifter, that is what they kept calling it. Basically the shift pattern is backwards and you don't need to let off the gas (or use the clutch?). I tracked back the sensor to the power commander and was wondering if I can just revert it back to stock since it feels weird shifting backwards. The gf, if she ever gets riding the 600 wouldn't know the difference between normal and backwards shifting so it doesn't really matter at this point...but for the ride home I was asking the guy if I could quickly swap it back to normal and he didn't know saying it might be part of the tune with fuel cuts or something.

 
#6 ·
:facepalm

If you care about her, you will sell it and buy her a Ninja 300 or Yamaha R3 to learn on.

A 600cc supersport is a bad starter bike for anyone, whether they are male or female, doesn't matter. Every new rider should start small.
 
#7 ·
I was in an accident last year that shattered my girlfriends leg. She'll never walk right again since she has a titanium rod screwed to her leg from knee to ankle. Words can't explain the fear I felt that running over to her motionless body wondering if she was dead or alive. And the guilt that followed post op when she had 22 staples in her leg.


I don't wish those feelings on anyone. Heavy shit.
 
#8 ·
And let me guess, she's 5'0" and can't even flat-foot it with a single foot, so you're going to ask about lowering it, too. Why not just get her a 1000, since you're already making poor decisions? If you're going to do it wrong, do it the right way and go balls-out. Or dicks out, if it's for Harambe.

Sell the damn thing, get her a smaller bike.
 
  • Like
Reactions: coopgt1
#10 ·
I think everyone above me covered this very well . Sell the bike and get something smaller for her .:gaah
 
#11 ·
I have no problem trading for a stock bike, actually that would be preferred for me and her since we don't need the mods. I hopped on the deal because a gsxr 600 for 1600 bucks that was running was a hard deal for me to pass up either way. I am not letting her ride the bike until she takes at least the MSF course to get a basic understanding of how to ride, so no worries there. It is currently just sitting in my garage until I figure out what all the mods are and if it is possible to convert back to stock...not going to let her SQUID out and become road kill! I started on a gsxr 1000 as my very first time on 2 wheels with the mentality that it can easily kill me if I sneeze...the bike was similar to this 600 in the fact it was a heavily modded track and stunt bike that I got for 2k. The thing for me is that I went into the big bike with the mentality that I have to be extremely cautious with it, but if need be it can help me escape from danger (lane splitting in CA) and I wouldn't need to sell a 250 to get a 600 to get a 1000 down the road. I have 5 years riding experience now and the one and only time I dropped the bike was my very first ride down my street and I misjudged the turn radius and fell lol. I didn't see anything past 5k rpm on the 1000 for a good 6 months until I got my confidence up. My plan with the gf is to do the MSF then slowly introduce her to the 600, all the while watching her actions...she doesn't have a need for speed and the bike fits her 5'6" frame so it is a good fit.

You can see the ad I have for the bike looking for a trade: 2001 GSX-R 600
 
#14 ·
Not gonna help you repair a bike that is too large for your girlfriend, sorry. If you buy her a smaller bike that needs some work, I will.
Hope this helps.
 
#17 ·
I am not forcing her on the bike and she won't ride it if she is uncomfortable with it. I could always keep it for myself and just remove all the stickers and paint it black. Her frame easily touches the ground on the bike so it isn't too big of a bike size wise...power who knows. She does have the same cautious personality as me when it comes to learning new things and I highly doubt she would ride at a speed that would make her uncomfortable regardless of the bike or cc it has. She practiced on my k3 up and down the street a few times, but didn't like how heavy it was or being on her toes...so she stopped riding and hasn't since.
 
#19 ·
You sound like a great boyfriend...

:rolleyes

Good luck, you won't find much help here, sorry to say.
 
#20 ·
Hard to tell from the video, but sounds a bit backfire ish. Is it running lean? Almost certainly needs a tune, or ditch the power commander and try that. As for the gp shift, there is a linkage attached to the and of the gear shift shaft coming out the side of the motor, take that off and turn it upside down then you're back to normal shift pattern. From the wishy washy sounding details you got from previous owner, he doesn't know shit so check EVERYTHING
 
#22 ·
I am not sure if it is running lean or rich. He said they had the bike tuned for upper rpm ranges >7k. I was thinking of getting the power commander auto tuner thing that constantly retunes itself. Seems like that might be a good starting point. The GP shifter he did mention I can just swap it around, but he was saying the day I was going home that he wasn't sure if the sensor on the linkage which plugs into the power commander would mess up with the shifts backwards. He was telling me that it might cut fuel/spark or add fuel/spark when it isn't supposed to due to the PC thinking it is going the other way. I honestly don't know enough about all the mods to know either way which is right or not.

I talked to him again after showing the video. Initially he just said the bike shouldn't be run without an airbox attached, but then he added
"It's possible one valve could be out of adjustment. When I adjust the valves I put them at the extremes because we want the most performance. In other words the intakes are just as tight as it can be and still in spec. The exhaust valves On the other hand I adjust loose while still in spec. Typically this keeps the bike running as cool as possible but gives it a very Snappy response"
"That particular engine and throttle body package is known for the under 5k performance issues. We rarely used that range."
"It is the original Suzuki throttle body and engine for 2001."

So based on what he is saying I guess my first step would be checking and adjusting valves into oem specs. Then either get a PC auto tune or take the bike to get dyno tuned to correct lean/rich as well as set up the GP shifting back to oem specs. Is it worthwhile undoing the REED valve delete and adding back the secondary butterflies, or is it ok leaving those as is? It seems I would need a new valve cover and upper part of the intake manifold if so because the VC is welded shut and the IM butterfly rail has been cut off so it can't connect to the throttle linkage anymore.
 
#24 ·
That popping you're hearing from the throttles is the Intake valves being open or not sealing when its firing the cylinder . That's why you can see yellow (Fire) around the edge of the butter fly valve. The engine has bigger issues . And @SheikYerbouti a dino tune won't fix whats going on with that engine . OP I would do a compression check and a leak down test to see whats going on .
 
#25 ·
GP shift is a mechanical shift rod configuration set up by reversing the lever on the shift spline, so that pressing down on the toe lever results in an upshift. Its just a reverse shift pattern. 1 up, 6 down.

If the bike has rearsets, you might be also be able to reverse it at the peg mechanism too. Either way, it is easy to switch back.

If you have clutchless upshifting (quickshift), there will be a cylindrical sensor on the shift rod. This is what you traced back to the PC unit. There would be no reason to remove this. Quickshift is a lot of fun on the street or track. You should be able to configure the mechanism to use the same sensor (Push I believe) with either standard or GP configuration.

Regarding fuel mapping through the PC, You can easily download different maps from the dynojet website to modify the way the bike runs (at any RPM). You can also easily customize/modify any map. I would start by uploading the stock map (called a "zero map"), which will put you back to the mapping that suzuki designed. May not be the most power if you have aftermarket pipes, but would allow you to evaluate your fuel issues without the complication of an aftermarket map.

My experience is that the 600 gsxr is very sensitive to mapping, and potentially the removed butterfly valves. none of this is rocket science, but you sort of need to get into it to understand how the mapping and tuning works. Took me a bit of tinkering to get mine running right (in my case, at high RPM).

Your bike sounds a lot like mine. I have the PAIR mod, with no ill effects.
 
#26 ·
I finally got around to checking the valve clearance.

The OEM manual specifies to the hundredth place, not thousandth place so I am assuming the .305mm exhaust clearance is still within spec since .31 is when the shop manual begins specifying shim replacement sizes
. Or would it be better to swap, if possible, shim #4 with shim #8 on the exhaust side bringing that .203 up and the .356 down? It seems odd that just a tad out of spec causes the backfire through the throttle body in cylinder 4. It is a starting place though, maybe combined with the tune was enough for the backfires to occur?
 
#28 ·
I ended up just swapping the Exhaust cylinder 2 .203 shim (152) with the cylinder 4 .356 shim (135). Then torqued everything to 10 NM with proper torque sequence. It brought the cylinder 2 clearance to .279 and the cylinder 4 clearance to .229. When I put everything back together and fired it up...the intake backfiring stopped completely. Bike rides very smooth now. I am unsure if the torque specs on the cam holders was just off or not correctly torqued down before causing all the issues. All the valves are now in spec and the gf even tried to ride it in an empty parking lot last night. She managed to get the hang of the clutch and did powered U-turns. She even tried adding a little bit of gas, but got scared to go more than like 10mph since it was the first lesson and her hand started to cramp up.

All in all, I have to say thank you to this forum! You managed to help me correctly diagnose the issue, change the GP shifting back to stock, and reassured me about the current set up of mods. Now my next steps with the bike is to remove the old stickers, add normal mirrors rather than handle bar mirrors, and add back turn signals to make the bike more street friendly for the gf. She is enrolling in MSF learn to ride program soon to get full training...the parking lot lessons are just her trying to teach herself the basics of the bike so she isn't embarrassed during the class lol.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top