RPM Drop at WOT Hot?

[Beerman]

No I can't read fuel pressure, but I will next winter so I can see you f it changes . I also was going to change the gas tank vent, I have the red one. I believe the black one is bigger, can't remember which one you should have that's something I will test when the snow flies, long wait

The black one is the updated part and it's quite a bit larger inside diameter - I switched mine out to the black one just to be safe.

 

[geez150]

I'm going to have to pay more attention to my rpm drop this season. I am still thinking it is more clutching/ belt related than an ECU / intake thing. As I was riding in 20-30f weather and had rpm and top end mph loss issues out of 4th lake in old forge hardly hit 100 mph, but the snow was very sticky. Then a few weeks later back at home in a corn field on more frozen type snow about 25-30f degrees with freshly cleaned clutches my sled was an animal not sure on rpm but quickly got to 110+. Then the following weekend up in tug similar degrees and snow conditions and I hit 116mph and had awesome pull. Again not paying much attention to rpm as things were happening quickly. I'm sure my intercooler was more plugged in OF versus the other rides mentioned but I don't know for sure. Just stating that the outside ambient temperature was all close in those different rides but the snow was very different hence different effect on the stock clutching of my cat.

 

[geez150]

Also from what I gather that return elbow won't have much to do with wide open rpm, more so at idle and low rpm operation.

 

[kviper]

Any body come up with anything more on this? Mine is doing the same thing. Worse on warm days!
Mine seems to run right up to 8,800/9,000 out of the hole and gradually drop to 8,400 and lower. Wondering about crank case pressure? 18 LTX

 

[1nc 2000]

I switched to the 8dn belt and heavier secondary spring this year and don't notice the rpm drop like I had last year.
It seems the 8jp belt is inconsistent with the heat.

 

[Crossfire12]

Any body come up with anything more on this? Mine is doing the same thing. Worse on warm days!
Mine seems to run right up to 8,800/9,000 out of the hole and gradually drop to 8,400 and lower. Wondering about crank case pressure? 18 LTX

I watched internal temperature 60 mph, 50 degrees, punched it 8850 up over 100 mph, maybe 5 seconds temperature went to 125 degrees, rpms dropped. Slowed back down cruising 60 again temps went back down. Running 16.8 psi, 270 hp this was on a 11 mile lake.I don’t think you can stop it. Didn’t do this with my 1100 turbo.

 

[kviper]

My rpm drops way quicker than that. I’am down to 8,400 by 60/70 mph all ready and lower in 30 degree temps. I think i’am going to work my way back to bone stock and see if or where I get back to a flat shift curve. I’ve been over all possible boost leaks, cleaned out all boost related lines and tried a couple different belts with no change so far.

 

[See n blue]

My rpm drops way quicker than that. I’am down to 8,400 by 60/70 mph all ready and lower in 30 degree temps. I think i’am going to work my way back to bone stock and see if or where I get back to a flat shift curve. I’ve been over all possible boost leaks, cleaned out all boost related lines and tried a couple different belts with no change so far.

Have you monitored boost to see if it’s holding psi?

 

[kviper]

Not yet. I will need to get a gauge!

 

[KnappAttack]

My rpm drops way quicker than that. I’am down to 8,400 by 60/70 mph all ready and lower in 30 degree temps. I think i’am going to work my way back to bone stock and see if or where I get back to a flat shift curve. I’ve been over all possible boost leaks, cleaned out all boost related lines and tried a couple different belts with no change so far.

Two things.

1. These machines have protections built in that when the IAT's get too high the power levels drop. The old 1100 did not have these protections.

2. When its warm out the clutches and mostly the belts get warm and stick harder in the sheaves dropping RPM. When its happening, put on a cool belt and try it and see what happens, the RPM comes back up, but only until that belts gets warm or hot again.

It's going to happen and RPM will not stay up. Don't get too overexcited. When it gets cold again it will all return. In cold weather I run 83.4G, warm weather I'm down to 78 and its still too low in RPM. All the Sidewinders the other day when it was 30F were down major RPM's.

 

[Crossfire12]

Have you monitored boost to see if it’s holding psi?

No boost drop

 

[kviper]

Interesting, I have a couple friends with winders and we were all riding together the other day in 32 temps. They were all down 100/200 rpm and mine was down 400+. Mine also drops off in colder temps as well. In cold temps I come out of the hole and see 8,800/9,000 then falls back to 8,400/8,500. It seemed to be starting this with everything stock and has gotten worse. Running full power performance clutch kit which uses stock cam with a white driven spring, think it's a dalton spring at 3/0. Stock with full power muffler. As I said I think I will go back to stock and see where it's at. Also thinking of eliminating the rollover valve and venting to atmosphere. I always have oil/water in the intake tube even after a 140mi day.

 

[Fleecer]

As already stated, I think the rpm drop is culmination of several factors, IAT, clutch/belt temps, conditions associated with warmer temps, safety features in the engine etc.

Left yesterday morning and sled was spinning 9150. In the afternoon outside temps hit 30f. Trail riding showed IAT consistently in the 50s and a quick pull would raise it to 107-110 degrees. By mid afternoon rpms down to 8750.

By evening things cooled off and rpms up to 8900-8950, but still low. I figured something was amiss so checked things when I got home a found another set of rollers have bitten the dust. Grrrrr

Checked rollers a week ago and looked new. Did lots of long pulls yesterday on the rr bed. Rode with several aquaintences running big iron all of whom took their turn attacking my Winder. The Winder fought valiantly and puts its skis to the front everytime like a loyal stallion. Unfortunately, I digested a set of rollers in the process...... still worth it.

I once thought it was the heavy weights ruining rollers. Yesterday, I knew it would be hot/mealy so put a setup with only 75 gram weights in the primary. I ate a set of rollers anyway. Cant figure out what causes this

 

[staggs65]

As already stated, I think the rpm drop is culmination of several factors, IAT, clutch/belt temps, conditions associated with warmer temps, safety features in the engine etc.

Left yesterday morning and sled was spinning 9150. In the afternoon outside temps hit 30f. Trail riding showed IAT consistently in the 50s and a quick pull would raise it to 107-110 degrees. By mid afternoon rpms down to 8750.

By evening things cooled off and rpms up to 8900-8950, but still low. I figured something was amiss so checked things when I got home a found another set of rollers have bitten the dust. Grrrrr

Checked rollers a week ago and looked new. Did lots of long pulls yesterday on the rr bed. Rode with several aquaintences running big iron all of whom took their turn attacking my Winder. The Winder fought valiantly and puts its skis to the front everytime like a loyal stallion. Unfortunately, I digested a set of rollers in the process...... still worth it.

I once thought it was the heavy weights ruining rollers. Yesterday, I knew it would be hot/mealy so put a setup with only 75 gram weights in the primary. I ate a set of rollers anyway. Cant figure out what causes this

I'm going to try a set of those G-force bushings that Stain is running

 

[See n blue]

Had same thing happen to mine running the 240 tune. Rpms were all over and first I noticed my secondary rollers were flat spotted fixed but issue was still there. Chased it all over trying to find a boost leak to find that both my mid pipe clamps were finger tight. Tightened those and added a turbsmart blow off valve and then I had too much rpms. Sled is running great now and I should mention that I run a XS825 belt. Found my stock helix to work best with my set up with a blk orange spring at 6-1. Stm weights up front with an Ulmer blk pink spring.