Wizard
Member
The short version is that my SRX seems like it losses power at the top end, but that leaves so damn many questions unanswered that I think I better tell the whole story! OK, I'd been riding a '98 SRX600 for about 8 years and I've messed with pretty much everything on it. Great sled, tons of fun. Once I made the mistake of letting wifey ride it and she loved it!!! So, you guessed it, I gave it to her and I got into an '01 SRX700. It's mostly stock with a Bender can. It sounds pissed off and frankly, I like it! But when I picked it up, there was one thing that bothered me; the guy had put reed spacers on and claimed they cleared up a hesitation. My 600 NEVER hesitated, but whatever, what could spacers hurt, right? Idk! But off I went. I got a few hundred miles in and it burned up #2. I tore it down only to find missing crank spacers on 2, also. Damn!!! So I bought a freshly rebuilt '01 block, cleaned my carbs, found the guy had mixed the main jets up a bit (he had the little one in #2), pitched the reed spacers and got her up and running early January. I've put maybe 300 miles on it since, but I'm just not liking it. I put a thunder shift kit on the primary and have it set around 4500 engage / 8200 shift. But even after dialing the power valves in last week, it just has no giddy up after 70mph. It's snappy as hell off the line; it gets to 60 in a hurry; it doesn't have a hesitation, but then it seems to fall off and I can hear that it isn't really in much of a power band. It just sounds sluggish. I guess what I'm wondering is where to look next. Should I change to '00 jetting and/or lean the needles a little or should I be looking into servo motor issues. It does open the PV's when I idle down under 1000, but is it possible that it isn't opening at high rpm's? Or if it's opening under 1000 rpm then it's working at high R's too? I've heard CDI's can go bad and not open the power valves, but I don't have a clue how to go about diagnosing that or whether this is an all or nothing scenario or if it could be opening some as I speed up but not all the way. I do know that if I unhook the servo it's worse, so it's definitely doing something. I need to see 110 on the lake if you know what I mean. Looking for some ideas specific to the '01, guys. Anyone else been through this?
staggs65
Moderator
sounds like a clutching problem if the powervalves are clean and adjusted properly. 8200 is a touch low but not too bad. should be 8500
mrviper700
VIP Lifetime Member
well kinda wide open question, need more specific information to help. I would say the servo is working as when you unhooked it and it was worse, tells me its working, usually if they open up under 900rpm it works at 6200rpm as well. The fact you say it only goes to 8200rpm grabs my attention, your peak for that sled is 8500rpm. So have a couple questions:
1.) whats the jetting in the sled now,pilots,needles,and mains?
2.) did you pull the plugs to see if the sled is running lean/rich?
3.)is the stock rear clutch stock with straight 47 helix and spring?
4.) gearing stock?
1.) whats the jetting in the sled now,pilots,needles,and mains?
2.) did you pull the plugs to see if the sled is running lean/rich?
3.)is the stock rear clutch stock with straight 47 helix and spring?
4.) gearing stock?
Wizard
Member
Most of my riding has been with the kids over the past 2 months, so I've only had a few chances to really open it up, but when I did it seemed to lack the kind of power I was expecting. It's nothing like the 600 is right now. Anyway, the pilot and main jets are stock (for an '01 according to this site) and I haven't looked at the needles, yet. I'll do that tomorrow. What should those be? I haven't looked close at the plugs yet either, I'll check those tomorrow, too. The secondary clutch and the gearing is stock to the best of my knowledge. I can dial the primary up to 8500; no problem there. But to be honest, sometimes it gets right up to 8200 and stays there but after 70 it simply doesn't sound right...but sometimes the "boggy'ness" comes in to play before I even get there and it only goes up to 7800 or 7900 from a dead stop like something's holding it back. I let off or ease into it first and then punch it and I get to 8200 right away, but eventually it still fallls flat. I jumped on the 600 a few times today to see how it was acting and it pulls good no matter what I try. I was wondering today if being in the low 20's (temperature) was the problem but it's not slowing any other sled in our group down at all. Even my kids phazer was staying with me today! Hell, it hit 75 easily!
mrviper700
VIP Lifetime Member
ya need to see what the plugs look like.
does it lose rpm after it gets up to 8200, does it fall back and to what rpm?
do a little more testing and check some of these things I have asked about, will be able to help then, otherwise my crystal ball is a little foggy on this .....lol
does it lose rpm after it gets up to 8200, does it fall back and to what rpm?
do a little more testing and check some of these things I have asked about, will be able to help then, otherwise my crystal ball is a little foggy on this .....lol
staggs65
Moderator
also, make sure your clutches are clean and all wear parts are in good working order. nothing binding, sloppy, etc...
Devilin AblueDress!
New member
X2 to on previous posts and just want to add try running with warmers off headlight unplugged. If your stator is getting weak (dirty/crudy flywheel wont help either) You may be running out of/low on juice to fire coils at higher RPM.
Wizard
Member
OK, I'll get back to you guys tomorrow after I look close at the plugs. One other thing that seemed odd as I went through the PV's last week is that while they all three had more build up than the '98 ever does, the middle one (#2 again, but this is a different motor / same carbs as when I bought it) seemed to have a lot of oily residue in the exhaust manifold (I removed the pipes) where 1 and 3 only had a little. All 3 PV's had a white slippery film on them that I was not liking, too. I'm running fresh 93 octane and klotz oil. Same formula in both sleds, totally different results.
Wizard
Member
@Devlin, thanks, that's the sort of thing I'm looking for. I need to isolate this issue because it makes so little sense. I'll give that a try. Btw, in messing with it since getting it back together, I've switched both clutches back and forth between the two sleds. I know the power bands etc. are dif' but nothing I do causes any troubles with the '98 while the '01 never works well once it gets up to the 60 to 80 range. The '98 has gearing from the mountain max to help it get off the line, but the '01 smokes it off the line so I know I have more horse power at low end. And seriously, I can hear the motor bogging once it's up to speed. It's not missing or back firing, but it sounds like a motor sounds when you give it half choke after it's warmed up. Bwoooooooh! Frustrating!!!
the secondary probably shift to fast and kill the rpm .....
tractordanp
New member
this is the exact same promblem i have with my 99 to the t. i have tryed differand clutch set ups even put back to stock set up figuring to start over as of now i am running bender cold air kit with jetting heel clicker clutch kit even went as far as new clutchs stock gearing sled pulls like mad off the line a mean after playing it acctually makes your arms hurt but it just sounds slugish not as quick as other but when i line up pull right away but only to 8100 ro so rpms
it does not have the top end my 98 had but deffinatly pulls off the line way harder
it does not have the top end my 98 had but deffinatly pulls off the line way harder
sideshowBob
VIP Member
A few years ago I had a similar issue on my 2002 SRX...no matter what tuning or mods I did it would not pull on top end....although 70 is real slow for these sleds and may indicate a serious engine issue.
My sleds issue ended up being a defective TPS.
Try calibrating, testing and if necessary replacing your TPS... Only present on the 2000 and newer SRXs and Vipers
Also when adjusting the throttle cable make sure at full travel you are only pulling throttle vavles as high as you need to .... Flush with carb bores as lifting the slides too high rotates the TPS more which in turn sends a higher voltage to the CDI that on my sled anyway can cause a bog on full throttle not unlike an overly rich main jet would do.
My sleds issue ended up being a defective TPS.
Try calibrating, testing and if necessary replacing your TPS... Only present on the 2000 and newer SRXs and Vipers
Also when adjusting the throttle cable make sure at full travel you are only pulling throttle vavles as high as you need to .... Flush with carb bores as lifting the slides too high rotates the TPS more which in turn sends a higher voltage to the CDI that on my sled anyway can cause a bog on full throttle not unlike an overly rich main jet would do.
bluemonster1
LIFE MEMBER ONLY ONCE!!!
simple things to do first.Try switching to a new belt.Next check if any springs are broke in the clutch's.Are there a lot of belt marks on the sheaves showing up.What helix is in there..what springs are you running in primary and 2ndary.What wrap are you using in 2ndary?? So many little things first.When was the last time bushings,slides,shoes,rollers been checked.How many miles on the clutch's.Sometimes the simple things that are over looked can be your enemy..Go thru the clutch's good.Next would be to remove and clean the carbs good.Start here and see if anything changes.Post back with results.
WedigSRX
Member
sounds simple, but by chance is the #2 plug the culprit ?
Simple check, but it is most likley something else....
Simple check, but it is most likley something else....
Do a compression test ! Mostly likely loss of power means loss of compression at the top end or possible ur cranks case seals are worn through ! 8100 is natural of ur riding fresh or deep ! Possible broken skid shock ! Bad bearing drive axle ! Worn splines ! Ur engagement should be at 4200 precise ! Worn belts ! Track tension check it all drive cog bearing or idle wheel bearing !
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Wizard
Member
Plug and compression report: 1 and 3 are chocolate brown. Likely using more oil than it needs to, but the setting is what my manual says. #2 is darker, yet, black in fact. I'm going to change plugs and re-check the PV's once more to make sure I didn't screw that up. According to the compression gauge I own, I'm at 130 PSI on all three cylinders and the motor had just been rebuilt with all new seals, pistons and rings so I'm not very concerned about that. I'm going to try Devlin's no lights idea and then move on to the TPS which makes a lot of sense to me. Wishful thinking, maybe, but I gotta try something. Is there a procedure in here for TPS calibration. My manual is for my '98, so I don't have that.
Wizard
Member
Is there a procedure in here for TPS setting/calibration? My shop manual is for '98 sleds, so I don't have that.
Devilin AblueDress!
New member
Wizard said:Is there a procedure in here for TPS setting/calibration? My shop manual is for '98 sleds, so I don't have that.
I thought there was a "how to" in the tech section but couldnt find it. Heres a link
http://www.totallyamaha.net/forums/showthread.php?t=78529&highlight=T.P.S
Might help.
Wizard
Member
My sled runs right with the TPS unplugged even though it passed the test in the manual with flying colors. I'm going to get a new one, but if it does the same thing with new what's the problem; the CDI? Also, I'm 99% sure the TPS from an FZ1,6 and R1 is the same, just looking for someone to confirm as the Genuine Yamaha one i found is for them but the seller isn't clearly stating that it fits the SRX.
bluemonster1
LIFE MEMBER ONLY ONCE!!!
there was an updated version of the TPS..don't get an older style one.