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Discussion Starter #1
i have a 99700(wifes ride) ive got it going not to bad i think 105 and change on the gun but it just plateaus there after about 1500' is there much more to be had from this ? it is completely stock except jetting and clutching(yellow/white with 10/58 polaris) stock secondary .im spinning 8100 is this too low i have heard as high as 8300 and as low as 7800. i get only 80 miles to a tank as well driving under70mph with the odd burst,the tcat gets 100 :)
 

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If it is a stock motor like you said 8100 if a bit high.
You should put on a breather. they help a LOT.

I piped mine as well. Again it helped.

As far the the mileage thing. Yeah they are REALLY bad.

Just whatch your jetting and try to run not too rich. Other than that they are a lot of fun. And 105 is good on that sled anyways.

Here's a view on mine
 

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yeah for a stock 700 that sounds about right...with some addons you can look to gain about 4-5 mph
 

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I'd try some 10-60's if i were you i ran my 95 twin pipe @ 8000-8100 and my friend ran his @ 7900-8000 wont hurt to try it.
 

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8100 is perfect for a twin pipe machine. 99 Stock is a single pipe.

On a single mine ran best at 7900.

Now I'm running 8200 on a twin. Seems to like it.
 

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I'm 285 #. My '99 ZR700 ran 107.9 mph on radar (glare ice) over 2000'. It did top out at about half distance. It was clutched, jetted, '00 CDI upgrade and vented airbox. A nice ride with the updates/upgrades completed. Poor gas mileage remained the largest sore spot.
 

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I had both a 99 and 00 ZR-700. After jetting / gutted air box / Goodwyn clutching both performed very well and achieved in about 10 mpg which is far better than stock.
 

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99 zr 700 stock calibration is way out to lunch. The biggest problem is the gearing. Came geared the same as the thundercat.It doesn't have the horsepower to pull that tall of gearing. Gear it down, use a helix with a steep starting angle, like a 60/54 so it won't trench off the line. Lots of guys run a 57/50, but the finish angle leaves it too flat on the top end. Add weight to the primary to spin it no faster than 8000 rpm. I also cut the heads to the minimum stock spec in the performance manual. Mine stock were .084 squish, cut them to .069. Cranking compression went from 128 psi to almost 150. This made the a huge difference.Jetting is also way too rich. With the cdi upgrade I run 290s down to -20c(0f). Mileage is really quite good , range is very poor. The tank will hold around 7 gallons from empty.
 

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Discussion Starter #10
modzr,290's to -20. that seems pretty lean. im running 320's now and the egts stay right at 1200 at around -15. what do you mean by the finish angle of 50 leaves it too flat on the top end?wouldnt it build easier with a lower finish(not upshifting as fast) i never did get the cdi box changed either. i heard the newer cdi's had less timming to them to prevent meltdown any truth to this? :ph34r:
 

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I don't know about the rest of you. But these are my specs.
D&D power pipes.
Black Magic MonoBlock head
PowerBreather
Stock CDI

Main jets 350 (good to minus 20 c then plug the breather)
Pilots 40
Screw 1.25 turns
Needle 3rd. Clip
Weights 10-60 polaris
Primary D&D orange 170engage - 305full
Helix Dalton 60-38
Secondary D&D Black
It comes in at 4600- 4700 rpm
Shift out at 8200 rpm

I'm not sure how you can run 290 mains. Even with the stock airbox the leanest I've run was 320's and that was at 1900 ft. altitude. Unless the newer CDI makes that much difference?

As far as the 60/54 helix, I'm not sure how well your backshift will be if you have your primary calibrated with ANY aggression. Did you find your clutching a little soft? Mine is pretty agressive now. But I like it that way.

I didn't have to touch my gearing at all. Tryed to but it was worse. Yes it's a bit tall, but on a long packed run I get full shift out on the clutch and still max at 8200.

The reason the tcat is geared the same is that the motor spins almost a full 500 rpm more!
 

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I am currently using a 136x1.75 track , 20/39 gearing, clutching that I have found to work the best(on radar and GPS) black magic twins, D&D power breather(waste of money), EGTs, and 2 degree timing key. I had the cdi upgrade done, and lost a lot of power, that is why the 2 degree timing key. Gearing made a HUGE difference.Yes the Tcat runs 500 rpm faster, but also makes 60 more ponies. Do not just jet to 1200 degrees on your EGT. You have to read your piston wash to find your ideal jetting , then read your temps. Probe location, and even the EGT itself can cause variations. 290 mains are very safe to 0 degrees F. You could even go leaner for short runs. The 700 motor does not make good power unless it is jetted right. Now for the kicker. Those of you who own a ZR 700 have the biggest underdog in almost every situation. It's a lot of fun to pick on unsuspecting people. Cutting the heads to spec also made a large difference. My 700 will run side by side with an F7 for about 400 feet, then the F7 pulls away slowly(as it should). The first time I put the long track on, I found the drivers were pressed on the drive shaft too far. The track was running 3/4 inch closer to one side of the tunnel. Cat warrantied the shaft, and coincidence or not, it gained 5 mph on top. All the 700s we looked at had this problem. Keep in mind what works for mine may or may not work for yours. I have spent a lot of hours making it work right, and it does.When I bought it, it would not pull away from a 500 in knee deep powder. After all the tinkering, I now really enjoy it.
 

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I'm curious. What's your top speed or your sled?
Where are you running? Trails, ditches, Mountains?

Before you cut your heads, what where you jetting at?
 

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Hey MODZR

In addition what altitude are you running at?

I am running a short track, at 1500 ft. That might explain the jetting.
 

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ZRJoe, we run everything but trails - borrrring! around 1700ft elevation. Before I cut the heads, they were around .084 squish. One head was .084 on one side, and .089 on the other. Cutting them to the service manual minimum of .069 helped a lot. A race shop told me you can go as tight as .065 with no problems. That's fine if all you do is run 660. Top speed with the long track is 94.6mph on GPS.(accurate to less than 1/10 mph.) Speedo showed around 105. Short tracked of course will do a lot more.
 

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Something doesn't make sense. You said your sled runs at 8000 rpm
You are running 20/39 gears. If you do the math with 12% overdrive cat clutch the BEST you should be running is 88 mph. Which makes sense on a 136" 1-3/4" track. - This comes direct from the Cat performance book and the D&D site.

Are you sure about your gearing???

I was considering running a 23/40 set myself.
<_<
 
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