I read & the books say flatslides better topend & better response & better gas milage if so than why does the 01`s get worst gas milage than the others??? My bro`s 99 is ported & piped & does better than mine?? But is it once you open up the case & trail port it it will do better?? Is it the timming also less on the 01`s?? Or is it all of the above??

could it be the rider??

touche. rider style can be a big difference. clutching is major as well as jetting your bros is just set up a little better possibly

My ZRT800 would do better on fuel than my brothers 800 Same year sleds.. I jetted my mains down 3 sizes from stock and had a BM clutch kit in it.. The other thing that I spent some time with was the secondary spring. For trail speeds I backed off the secondary spring to the 2nd hole (from the lightest setting). This allowed the Ratio to be lower and pull then RPM's down. It kept the engine running at lower RPM when crusing. Under WOT I still would get to my 83-8400 RPM's that I wanted. I had a roller secondary also but with the lower RPM's it didn't feel sluggish.. I rode from Hearst Ont to the Sault Ste Marie Ont almost 500 miles and was getting 13 to 14 MPG, keep in mind fuel stops are spread out so I was not into the happy handle to much.

I would expect the 900 and 1000 T-cats should be able to get 11-12 MPG

How does you're sleds clutch engagement rpm /trail speed rpm compare to you're brothers sled?

I am only replying to this because I have 2 friends that are die hard triple fans like myself.

We do a lot of trail riding in the 50-60 mph range with a few 100mph spurts. The 2 T-cats that my buddies are running are 99 and 02. The best of the 2 was 9mpg with the 99 model and 7mpg with the 02.

As far as I know these are both stock with studs ( 192) and are very dependable machines. The fuel mileage on the 02 was so bad he sold it at the end of the 05 season. According to what was said when he asked about the bad fuel mileage, he could have rejetted, but he said he did not want to screw with the reliability. the guy with the 99 is rejetted and need snow to find out the diff.

I have an 809 DOO and can get 13-14mpg running with the two. If you people can help with better fuel economy for my friend , let me know.

3inaline

I,ve heard this gas milage issue come up in a few posts in here, none of my friends have experienced this. My trail ported ZRT 900 used the same amount of fuel as my friend Mikes 1999 machZ , and the same or less than another friends ZR800, and the same as another friends 2000 TCAT. I wonder if Cat had some cdi's that were worse than others in the late model tripples?

Engagement was close to the same, around 4800 to 5000. Typically on groomed trails I would run 50 to 60 MPH, RPMs were 6000 to 6500 If I remember correctly. I can remember having the secondary spring tighter and at these speeds it would put me right a a shift point, tip in and the RPM's would flair and I would accel and back out I could not hold speed very well. So the second hole on the secondary was the best. I could keep decent speed in the trail and rpms were resonable to me. When I went to WOT it would backshift and pull good.. I don't know how the 800/900 compares to the 1000.

If the flat slides are as rich as the rounds you an down jet. Like I said I was down 3 sizes from stock and had ridden in -20 deg and never had a issue..

Not sure on CDI and timing advance. If the 2 stroke is the same as a Auto 4 cycle then advancing timing would be a + for fuel economy..

Well I think the ported motor case in all with more timing is the key, I did jet down one size but will go one more, other guys sat 300 mains on the flatsides, are clutching is close but dif weights cause he is piped I do our clutching I do a lot of grass racing, I dont beleive it is that, yeah I have a happy thumb, cause it is so responsive compared to his. I did gut my box out too, I have a noise up front I think the bearing is bad on the drive shaft & the track clips are getting bad. I am waitng for my keys to come from D&D that I orderd a week ago, it took them three days tosend out wow.

4800 to 5000 rpm engagement seems VERY high , my 900 comes in around 4000, why so high?

I come in at 3800 to 4000, the 600`s yeah 4800 to 5000, but not the big blocks.

THE SPRING AND WEIGHTS WERE CHANGED. 192 STUDS THIS WOULD EXPLODE AT 4800..

with stock pipes and 300 mains I was getting between 9-11.

with pipes and 400 mains I am getting about 9-10.

A good clutch setup will help with mileage.

the worst thing you can do for a tcat is leave it stock.no fun to drive and very hard on fuel maybe 9mpg if lucky. i was alaways using 3 to 4 $ more each fill up after clutching, jetting i would get the same as my freinds efi f7 no bs.

Bad fuel economy was due to bad factory jetting. My 99 TCat 1000 with roundslides, D&D triples, powerbreather, gearing, clutching, Delta 2's, tempaflow, normally saw 10-12 mpg riding hard. Yes I used egt temp gauges and spent half the winter getting the jetting right, needles, needlejets, mains, and pilots. Once and a while it would drop to 9mpg in poor trail conditions. Very reliable too, rode it for 8500 trouble free miles!!!! I once rode with a completely factory stock 2000 TCat that would be lucky to see 7 or 8 mpg. My machine would dominate his from start to finish too.


Just another note, when I bought the Tcat in fall of 1998, I sold my 96 ZRT 800 to a buddy of mine. He normally got 13-14 mpg with that thing, and that jetting was factory stock!!! How AC completely messed up the jetting (on the flatslides) with the newer ZRT800 and TCats I'll never know. Seems like they would have done some testing before releasing them to the public!!!

I've noticed the same thing on my '95 ZRT 800 vs my '01 T-Cat. It was common to get 13-14 mpg w/the ZRT while my T-Cat averages around 10 mpg.....trail riding conditions.

JMY

Like I said before my brothers 99 is ported case ported & piped gets around 12 riding hard, I beleive they do need portting & timming, & jetting, but the two sizes that you normally go isnt like cat was far off they have to be rich from factory to cover there ass.

Answer me one thing does it have stock jets, if so jet it up. This may sound crazy but my mostly stock 99 800 has a 420 main (ride in Mich) and when I stop at the gas station I get the same amount as my bro's ZR 800. Alocal guy that builds Cats told me to try jetting up because A-C made them run so lean they would not make enough power to burn itself up. All I did was jet up and the sled is a whole new machine. It may sound crazy but it works, it now feels like it could take more the plugs show lean when checked from a long pull across White Lake. ALSO MAKE SURE THE CHOKE CABLE IS NOT BEING PUSHED DOWN BY THE AIR BOX. Cat sent most of the sleds with the choke half open. I did get that fixed first but the sled would only get about 5 to 7 miles to a gallon and go threw oil like crazy. Try to move the choke cable by grabbing the top and the bottom and moving it back and forth should move easy.
Hope this helps, good luck

if you send me your motor, i'll send you mine. it's a 600 triple. it'll GREATLY improve your mileage. i'll even pay the shipping. fair deal huh? lol

CAT CAN DO who you refering to mine is a 01 not a 99. I sold the sled anyhow.

CAT CAN DO who you refering to mine is a 01 not a 99. I sold the sled anyhow.

600`s dont get anybetter gas millage I had two of them duh.

Something is very wrong with that 2002 Tcat for it to gt that poor gas mileage ... My 2000 Pantera's engine and carbs are bone stock. I routinly get 12-14 MPG and that is after going to to a 24-40 gear and chain. My 2002 TCat is built with Pipes, New heads, clutching and running 430 mains ... and it has never gotten less than 10 MPG Trail riding ... and have gotten as much as 14 MPG when being conservative with the thumb. ALTHOUGH ... on Back lake (NH) with a weekend of primarily wide open runs, I have seriously sucked gas ... down to about 8 MPG.

I suspect the clutching on those 2 machines is the issue.

My clutching is awsome, give it a break the 01`s would do better ported & timed I know that. I checked my milage & was getting 12 plus mpg.

You guys with the Thundercats should try the Tempaflow. It really does work and easy to install. You jet for a baseline at -20F, and the mixture leans out from there the warmer it gets. Keeps the engine running crisp, doesn't matter if it's -15F or 30F out. Plus, fuel economy becomes much more consistant, at the top of the scale. Of course the range was improved as well, by 10-30 miles per tank. I used it on my 99 Tcat with pipes, powerbreather, jetting, gearing, clutching and it worked awesome!

snocrazy, how many miles to a tank were you gettin on your 99 tcat

cat-can-do, i find this very hard to believe if they were sent out too lean to make any power and burn up, the mixture would misfire and the sled would crap out. if this was the case you could go leaner and leaner and never have to worry about a burn down. i run 420 in my tcat and have run 410 in it but would not run any lower than that for all around use. when jetting you have to go by piston wash 1st that is the best indicator to tell you how your engine is running (rich/lean) you can use the plug electrode but it is much more difficult to read and depending on the type of plug used may not be accurate. when you jet up to a rich mixture above 14:1 your engine will make more torque but you will loose hp on top. try a set of ufos and you will soon realize this. the thing will suck fuel faster than ever but it makes gobs of power down low. but you wont get better fuel milage. bigger jets =more fuel =less mpg.

I was getting 10-12mpg, so range should have been 100 miles-but I always looked for gas much sooner. I didn't do any internal mods to the engine, just bolt on pipes, powerbreather(with all caps open), D2's, Tempaflow. I ran the 420 mains(for pipes, powerbreather, and tempaflow), Q4 needle jets(Q8's were stock), 35 stock pilots, clip on 4th position-richer. I jetted by piston wash and egts. I believe the egts were reading 1275max in the 7000 rpm range, and once seen just over 1300F. Probes were 4 inches from piston. Ran this machine for 4 years like this without a single burndown! Rode in temps as low as -20F. Never even removed the heads! And, better economy and much more power over stock. I sold this machine to a buddy 1.5 years ago and it's still running strong.