TOP SPEED ISSUES please help.

[jgustman]

I'm having top speed issues on my 03 limited rx-1. I have a ecp and evac kit, only pulling 114mph on the speedo at 10,200 rpm. I have Notched supertip weights, 14.5 rollers, OSO primary spring and stock helix with pink spring at 70 deg. twist. 1/2 inch sag in track with no weight and extrovert drive sprockets. I want to know if it is due to running a 1 3/8" lug fully clipped snocross track or just clutching. The snow conditions were on a 1-2 inch loose/packed snow on a groomed trail. I saw 119 and climbing on the speedo when new, completely stock, now has 750 miles on it.

 

[grader]

first your not fully broke in yet, second the 13/8 track will cost you some top speed, third the rpm should be about 10500 for max. speed.

 

[jgustman]

I know the deep lug track is costing some speed, but I'd like to find someone with info on how much is lost. I was only pulling about 10,000 at best when it was stock when breaking it in and easily pulled 119 and climbing fast. It must be the track because it pulls hard to about 105 and kind of falls on it's face. I was going to do a swap back to stock weights and springs to see what happens to verify any clutching difference on top end but would like to save the trouble if somebody has some knowledge of how much deep lug tracks affect top end. I would imagine the stock track is 33 lbs. vs. 41 lbs. for the deep lug I have now.

 

[pro116]

what is your rpm's.I would go with a silver secondary spring try between 70-90 degree's.

 

[black john]

top speed

check your clutch alinment. i have found that you can pull the center to center closer to gether with the fillter mods. just pulls that much harder. i had the same problem it just killed the top speed.

 

[lippy]

1/2 inch sag to tight. I just had same problem go with 1 3/8" sag you will find what you are looking for

 

[jgustman]

Thanks for the info so far...May be a stupid question, but how do you get the center to center closer together? I thought the RX-1 motor was rigid mounted, but I suppose there is some room for adjustment. Also I have tried the silver secondary spring at 90 deg. twist and wasn't pulling quite as much rpm with same speed results. I have the secondary offset at 16 mm, as close as I can get to 15mm for now and fixed, not floating. Clutches are aligned. Like I stated earlier, I lost mucho top end with track switch and clutching changes. I don't believe it's in the clutching though, as the rpm's are where they are suppose to be from holeshot to top end. I was worried the 1 3/8 inch track would hit the tunnel protectors and slow top speed down if I ran any looser than 1/2 inch sag. My fear is that it's just becoming a big fan over 100 mph and the air turbulance/resistance is what is holding the top speed back. I guess it's a ok trade off for the accleration and deep snow performance, but I don't think 15 mph on top end is acceptable if most people were seeing 130 on the speedo on top end with a stock track. Like I said before, I may try the stock weight setup and see what happens to the speeds, was hoping somone will step in and say they had the same problem going to a taller lug track and if this is normal.

 

[Turk]

I gained 12 mph switching from a 1.18 full block to a 9830 on my rx-1. Rpm,s should be 10,200...the motor falls off after that. Go back to 60 degre wrap with stock secondary spring or try a silver at 80.

 

[Fullback]

I think your track is the biggest culprit. Plus you aren't broken in yet. My RX1 was fastest on top end with the stock track and 192 studs. Now I run a 136" Ripsaw with 168 down the middle on a T-cat skid with filters and clutching and my top end is down but as far as acceleration there's no comparison.

 

[jgustman]

Turk, thanks for the info. I believe I may be right on target with a fully clipped 1 3/8'' track for top end if that's the case.

 

[LazyBastard]

On the STOCK TRACK, you could get severely unreal speedo #'s in ANY condition. That track was SEVERELY insufficient for this sled. You're running on loose top over hardpack with a track that grips. That speed seems a *little* lower than what you would expect with a *normal* track (I would say 116-117 with a ripsaw), but then taking into account that high profile track and I would have to say that you're doing pretty good (I would have guessed about 110-112 if you didn't give the actual reading).

 

[jgustman]

That's a relief, I was looking at going back to my stock weights tonight and doing a test run, but I don't think there is anything to gain if the rpms are right where they are suppose to be. I'd assume the clutches are fully shifted out, but haven't marked them to see for sure. The notched supertips have 5 washers in the heel and 2 in center and one in tip. Any better suggestion on weight/washer placement. Engages at around 4300 rpm, jumps to 10,500 and pulls back to 10,200 right now.

 

[lawndoctor]

My clutch alignment; center to center, offset and twist was off quite a bit. You can move 3 of the mounts to line it all up. I picked up 300 rpm after I adjusted my alignment and there is a noticable difference in performance. I use the Sled Pro tool and it works extremely well. In addition I run Supertips and the Silver wrapped at 90 works very well.

 

[black john]

top speed

you can have the best clutching it the world and it is a waste of time if you are not lined up right because it just will not work. kind of like a dog chaseing its tail.

 

[number1kyster]

my father has an 03 with nearly 11,000 miles on it. It has the ripsaw and on hard park i could get 121 out of on the dream o meter. It is faster than his 05.