98 srx 700 top speed

P

Pauljones

New member
Joined
Oct 24, 2009
Messages
90
Age
50
Location
Manitoba, Canada
Hi Boys,
Hope everyone is as excited as I am for the upcoming season. Thanks to everyone on the forums who have helped me out over the years. For this year, I would like to see what clutching and gearing would get me the highest speed on the lake over a 10 mile wide open run. I have the following clutch parts:
89a-10
8bu-10
8dn-20
8dn-00
4 different helixes
my gearing has been changed over to 13 wide hyvo.

Over the past few seasons I ran 23-39 gearing and played with 8bu-10 and 89a-10 for hard acceleration. It was fun but the sled would have a hard time going over 180km/h (110 mph) on the speedo. I would like to bury my speedo this year on the lake 120+ mph. My motor is stock, suspension is stock, 1'' track no picks. What is the ideal gearing for top speed, should I go to a 37 tooth bottom (or more). Also does anyone have any ideas for a starting point on weights, rivets, helix angles, and clutch springs. Thanks.
 
Pauljones said:
Hi Boys,
Hope everyone is as excited as I am for the upcoming season. Thanks to everyone on the forums who have helped me out over the years. For this year, I would like to see what clutching and gearing would get me the highest speed on the lake over a 10 mile wide open run. I have the following clutch parts:
89a-10
8bu-10
8dn-20
8dn-00
4 different helixes
my gearing has been changed over to 13 wide hyvo.

Over the past few seasons I ran 23-39 gearing and played with 8bu-10 and 89a-10 for hard acceleration. It was fun but the sled would have a hard time going over 180km/h (110 mph) on the speedo. I would like to bury my speedo this year on the lake 120+ mph. My motor is stock, suspension is stock, 1'' track no picks. What is the ideal gearing for top speed, should I go to a 37 tooth bottom (or more). Also does anyone have any ideas for a starting point on weights, rivets, helix angles, and clutch springs. Thanks.
Click to expand...

What RPM's are you holding at WOT?
 
I don't know if this will help but this is my set up;

Hauck Stage 4 clutch kit, I never got to involved with clutching specs because I got this kit when I first bought this sled new, and it's been a great kit for trail and lake.

And I went one tooth larger on my top gear, can't recall the tooth count, it's been 16 yr. This also helped the sled out of the hole for some reason. We always race on hardpack where there is some spin.

I've had really good luck with this setup, drags and top speed. It gps'd 117 on packed snow.

I think most important is clutch/sled maintenance thou, all the mods you do are worthless with even one bad bushing in the clutching. One bushing that seems to need replacing more than any other is my inside bushing in the secondary. Every 1500-2000 miles, I can't feel the difference, but I ride with a couple other SRX'S and when they start winning our impromptu races, I replace that bushing and its back to the lead.

Good luck.
 
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hey Paul..your whole sled has to be in perfect tune from front to back..clutching,skid set up,ski alignment, bushings/bearings up to date,pv's adjusted properly,compression,etc.I got my best speed on ice,a little snow will slow you down(has to be packed and smooth also).Motor will run from one day to another day different due to temps,humidity,jetting..etc.
You riding yet,not much snow on the ground for me to really ride South of the City.To early to try the rivers yet.as you have heard on the News the sledders this season who have already gone thru the ice and nearly died...
 
look, there is so much more in setup to achieve big speed than clutching and gearing. i believe driver weight, traction, and suspension set-up is just as important. i posted three years ago i ran 110 on a stalker in 1000 f.t. with 8bu-10, lite driver, stock skid but lowered and on ice. the weights you posted the 8bu-10s are your best shot. they are your best bet. paul, i think you need to talk to jabber(DAN). he runs at all the big speed runs and has set a record on a 600 srx. lot more to this than weights and a helix. 3:16 (yammie tony)
 
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Are you running ice scratchers? 120 on bare ice (hard pack snow for that matter too) for that kind of distance with out them the friction alone will slow you down. I have gotten mine good and toasty on much shorter pulls, Have read on here of guys clips melting right into hyfax afterwards.
 
Not trying to set any type of srx record for top speed. Just going to try to get the highest speed possible out of MY srx by modyfing the cluches and gearing, not interested in major mods to the skid or track. I do know that the stock clutching and gearing that came on the srx was a compromise between acceleration, top speed, and backshift (any clutch gearing recipe is always a compromise between these items). If Yamaha had decided to simply give the stock srx700 clutching and gearing that would result in the highest top speed (over a very long run 20 000+ feet) what do you think it would have been?

Could not agree more that maintenance makes a huge difference. My clutches come apart every season (bushings are changed in primary and secondary, yes I made a clutch grunt tool). All bushings in the skid have been replaced with oil-lite brass bushings personally made by me. Its amazing how different a pro action skid is after this mod. Thanks to BetheViper for the great posts on this subject.
 
Another way to state what I am looking for would sound someting like this:
"Your not going to set any srx700 speed records, but if all you want to do is bury your speedometer, over a very long run, on a well maintened stock srx700 with a 1'' track, this gearing, these weights, and a helix around this angle would be a good starting point"

For me, to change the gearing, its about a 1 - 1.5 hour job, with new chaincase oil to boot. Really hoping to get some feedback on what gearing would be best to start with. I also realize I am going to have to test, just looking for some starting points and/or things I should be thinking about.
 
well I try to avoid these kinds of threads because 1 persons opinion goes against the opinion of others and then the arguing starts. I am just going to say since we are talking about yamaha weights, if you look at the weight charts yamaha provides you can see there are other weights that apply more shift force (higher kg) for a longer duration at a higher force then 8bu-10. I know everyone thinks those are the ultra fast weight but theres others that will out do them right from yamaha. All the weights are compared the same,empty,no rivets, 7500rpm with 15.6mm rollers, so the chart becomes easy to see where you can improve. I would encourage you to look at the charts and play with 8ca, 8bu-00. 8ca will require more rivet weight,but they work super! I have a couple 8bu set ups I have used in past so I will pass those to you.

In reading your post and what your asking for is you drag race AND want some bigger topspeed on the speedo, so your going to have to make a little bit of compromise there as it requires a differnt sec. set up for each, the primary can stay somewhat the same.

try 8bu-00 weights with .8 alum in first hole, 4.5 in the tip, y/w/y(45/128kg) primary spring, 50/44 helix with green sec at 60-70 for fun. You might get away with a w/w/w primary(45/120kg), but in a 98-99 srx they dont make quite as much power as the 2000-02 does. 98-99 make 137hp on avarage, the 2000-02 make right at 140hp.

for your top speed running try same primary, 50/44 helix with red sec set at 60, youll need to lay into the gas slowly so you dont pull the belt but this should bury your speedo over that long distance with a 23/37 gear ratio. Run atf in chaincase, set chain slack to 1 inch movement back and forth total on backside of chain.Keep the track slightly snug as the looser it goes it will balloon up and rub the protectors under the gastank in the tunnel, slowing your mph down.

I would get a couple extra helixs and play with shallowing out the finish angle even more then the 44, get some 42,and 40's,(49/41,51/37,50/40 I have used in the past with good results also) youll be able to loosen up the sec clutch spring tension as the shallower helix angle will squeeze the belt tighter and you dont need the spring tension then, this equals more speed. You will then likely need a little less shift tension on front spring as well to keep the rpm right, you can also add a washer or 2 to the tip rivets.

play with a the red sec spring set loose and watch what the speedo will do!

Just some ideas to play with. Everyone has thier own way.
 
Thanks, Mr. Viper exactly what I was looking for. Anybody have a 37 tooth 13 wide hyvo gear they are willing to sell? GM Dexron ATF fine? or is there a specific atf people use?

I have been posting in mph since I know most members are in the USA, but my sled is Canadian so the speedo goes to 200 km/h (124.3mph) so it is a little more to go for.
 
My thought on trying to get max speeds with any sled is to make sure everything on the sled is running true. Friction is a killer at speed. Check alignments, track, shafts, gears, clutches, skis. Make sure the engine is healthy and clutches are smooth and not binding in any way. We have had our best results with 13w gears, stock gear ratio but using larger gears. We do not run a tensioner! Our 700 stocker ran high teens in 2000 ft every weekend we ran. We tried many different clutch set ups and choose to run 8BU10's I'm not here to start a pissing match over what works better but this was the ticket for us. Our results where very good! One thing to keep in mind is that you rarely run an empty weight. The shift rates change a lot with weight added and we alter the BU10's considerably with rivets and added custom made washers along with a bit of grinding. You should have no problem getting that sled to bury the needle! It takes a bit of attention to details!!!
 
8BU-10,S ARE THE BEST '' YAMAHA '' WEIGHT FOR ACHIEVEING TOP SPEED. THE 8BU-00 WEIGHTS ARE THE BEST WEIGHT FOR ACHIEVEING THE BEST .E.T. (MY FINDING) I WON,T START A PISS MATCH EITHER. THIS IS FROM TESTING ON GRASS, ICE, AND TAR WITH TWO SRX,s. ONE CAN RUN WHAT HE LIKES. again, this is in finding only 3:16 (yammie tony)
 
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YAMMIEGOD3:16 said:
8BU-10,S ARE THE BEST '' YAMAHA '' WEIGHT FOR ACHIEVEING TOP SPEED. THE 8BU-00 WEIGHTS ARE THE BEST WEIGHT FOR ACHIEVEING THE BEST .E.T. (MY FINDING) I WON,T START A PISS MATCH EITHER. THIS IS FROM TESTING ON GRASS, ICE, AND TAR WITH TWO SRX,s. ONE CAN RUN WHAT HE LIKES. again, this is in finding only 3:16 (yammietony)
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I have an 01 and I’m running 8bu-10s with 4.5 in each hole, 1” hacksaw with 96 picks, 51/43 helix with green spring at 70, but my RPMS are still too high at top speed, sitting around 8750. Gearing is currently 22/38. Am I better off running stock gearing? Should I change helix angles?
 
TheFridge said:
I have an 01 and I’m running 8bu-10s with 4.5 in each hole, 1” hacksaw with 96 picks, 51/43 helix with green spring at 70, but my RPMS are still too high at top speed, sitting around 8750. Gearing is currently 22/38. Am I better off running stock gearing? Should I change helix angles?
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That's not much high as the sweet spot is 86-8700.
Add another gram to the weights. you can use bolts or order heavier rivets from Hauck.
I've used a mig welder to add a little weight many times.
 
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