Well I went to my first radar race ever with my new sled this year and I was extremely dissapointed. I really don't want to tell anyone the top speed it did at the 1/4 mile.

Where do I start? I have a 98 EFI ZR600 L/I. What should I do to get this thing running better. I don't think anything has been done to it beside a clutch kit.

Before the race I noticed I had lost all bite out of the hole. I didn't bother registering until I noticed that the bolts were loose on the jack shaft support. Me and my buddy tightened the bolts and it seemed alot better. The top end speed was pretty disgusting. I would think that I should easily be in the mid 90's with this sled?.

I emailed D&D about pipes, they don't list them for a 600 EFI on there site. Ninety percent of my riding is pure trail but it would be nice to be able to compete with some pride at the radar races every now and then. EFI seems amazing in the trails and the power seems to be there when needed coming out of corners. I am extremely surprised the sled ran so poorly considering its amazing quality in the trails.


Are you ready for the this?????????
My top speed was 121 Kms at 1/4 mile! I'm going to go hide now and never show my face again. I thinking about seeing if I can buy back my old Summit, atleast it wouldn't be embarrasing when you run a speed as such. I still love Cat but I'm just shocked and a little jerked off!

I do think I need to have the clutches looked at. I think the bolts had been loose for some time and has created issues with both secondary and primary.

just so others know the speed, the conversion equals about 75mph.

sorry to hear about your loss man[no pun intended]
i know a buddie of mine had a 2001 zr600 efi and it
was not any match for my xc, but it wasn't that slow.
you definately may have something wrong with the
clutches there. aftermarket parts for the efi sleds if i
remeber right were a little hard to find for the fact is
that the ecu[brain]would have to have a chip put in it for
any real mods. i also had a buddie that had a 2000 zr600efi
with a bunch of black magic stuff on it[pipes/reeds/chip/etc] and
he claimed it did not run a whole lot better than stock. if i
were you i would definately have the clutches looked at and
clutch alignment. sounds like its not upshifting all the way.
anyways, good luck!

First i would not recomend running D+D pipes unless you dont mind dropping pistons on a regular basis my friend went that road with his 99 600efi needless to say it stock again. top speed can be affected by alot of things first check the clutches how many miles do you have on them?? weight bushings good, rollers? ccenter to center, alinement, belt deflection, condition of the belt, hows the track alignment, is the track to tight. My friend had a 98 ZR600EFI CC and it seemed very fast stock, many guys with newer sleds had to have a double takelooking for pipes etc. i dont know why his seemed faster than most he just must have ended up with a hot one. take care of the easy stuff first before you start throwing parts at it.

Few things to try before you go the whole pipe/chip/clutch kit route.

First, the '98 sleds had a feature that allowed you to change the fuel mapping before you drag race. I believe, (its been a while) that if you "blip" the throttle 3 times full, before you drag, it changes the fuel map. I had '98 ZR's and it worked.

Second. Try gearing the sled. My brother went the whole D&D pipe/chip/clutch kit route, but it really didn't make a huge difference until it was geared. Once he geared it, the thing hauled @ss. It would give 700's and 800's fits.

Good Luck.

that is really surprising, although not as fast as my 98 xc600, my 98 zr600efi le was not too shabby either when stock. The easiest thing I have done to it was to buy the hot rod chip for the efi about 250 to 300 bucks. pretty cheap for 8 hp and it actually improves economy under normal driving conditions.You cant do this on later efi models. Also I had a buudy clutch it for me, not sure on set up only that it engages at 5300 and it has a bm clutch kit. I still top out about mid nineties on the gun, but mine isn't clutched for top end. It is a rocket from 0 to 90 though gets there very fast and pulls hard from any speed when punched.

My past experience is that spending lots on aftermarket mods isn't always justified by what you get in return. Keep it cheap and simple and the reward is usually that much better

I had the sled that Jay was talking about and yes the thing really came alive when I geared it.
Had the D&D pipe/chip/clutch kit combo on it coated pipe and geared to 22/41. Yes it did surprise many MXZ670HO's and some 800's back in that year, ran right around 86-88 in 1000' and would be close to the century mark at 1320.

If you had the jackshaft come loose I would check the clutch alinement, bearings for the jack and drive shaft, then try to figure out why the shaft came loose. If you rode it like that, the belt is probbly bad. A sled that old probbly needs clutch rebuild if you havent had one done. A new belt will make a huge difference in performance.