boost with miles, freshen top end or go to 9R boost?

[goforbroke]

I have a 2023 boost that has been flawless and soo much fun. Never a problem and about 1400 miles. Have slp can and ibexx intake kit, otherwise stock. Warranty is going away this summer. I think I will keep it for my main ride one more year but I wanted to freshen up the top end, clutching and maybe make the bottom end more responsive. Wondering what I should do. 3 options

1. new pistons new reeds, trs valve and new clutching. Polaris pistons $750, speedworx reeds at $130, trs valve $425 and will stay with p-22 what clutch kit? clutch kit cost $500 = $1800

2. bikeman turbo mod, bikeman tune, bikeman clutch kit, new polaris pistons and new reeds. Bikeman turbo mod $1000, tune $500, clutch kit $550, Pistons $750 bikeman reeds $140 = $2940

3. Polaris 9R cylinders, valves, and pistons, slp head, clutch kit and tune plus reeds or a 9r boost = $4140

I will check intake while in there. What option will be more reliable and more fun?? I have a 2024 lynx turbo r (kmod skinny 165) and a 2024 polaris 9r (stock, just doing clutch kit) that I sometimes ride and my adult kids ride. Boost is my favorite ride still. Not enough different on the 2026 to snowcheck one so want to do something on the boost to make it fun and hopefully last one or 2 more years. Hopefully someone has done some of these options and can gvie me advice. I ride 8-10k and mostly just 1' plus powder days about 500 miles a year.

 

[Teej83]

If you are only keeping it one more year why on earth would you even consider the $4k option? If money means that little, at least get a fresh sled to do it on

 

[goforbroke]

If you are only keeping it one more year why on earth would you even consider the $4k option? If money means that little, at least get a fresh sled to do it on

Currently sled is tough to sale, maybe worth $11k?, whatever I put into won't make it more valuable. Will likely keep for another year after that for my family to ride. I spent enough on the lynx and 9r this year that a new sled isn't in the cards, but 2k to 4k is doable.

I haven't been around any other sleds with tunes or 9r boosts. I figure if I am already spending almost $2k, if the 9r boost or bikeman turbo are big enhancements, I might as well do that. Goal is a fun sled, bottom end being as important as the top end for me. I love snowmobiling, been doing it 40 years now. It is definitely a money pit, but sleds these days are AMAZING.

 

[JH@CM]

If I had a few grand to spend in your situation I'd sell the 23 and buy a newer boost with fewer miles.

 

[Teej83]

I have to imagine a great tune with clutching would be more than enough then. Given how tunable turbos are i don’t know what you’d be getting with the expensive 9R option you couldn’t with an intercooled, tuned, clutched 850

 

[goforbroke]

I have to imagine a great tune with clutching would be more than enough then. Given how tunable turbos are i don’t know what you’d be getting with the expensive 9R option you couldn’t with an intercooled, tuned, clutched 850

Any experience?

 

[Tjtwenty]

I'm in the exact same situation. I have a 23 as well as a 24 boost. I prefer to ride my 23 though. Selling used sleds for so cheap doesn't make sense to me. I'm also considered the 9r cylinders or just a fresh top end. I've already tuned, clutched, exhaust, suspension on both sleds. Also looking for real world experience from anyone running the bikeman turbo mod in tight, technical trees at 9-10k elevation

 

[alorenzanthony]

I ride a 23 boost 155 the best mods i have done was the 25 boost reflash and 3.25 track.

 

[FlynHigh]

Since you want to make it more fun and not necessarily all out crazy I probably wouldn't do a 900 kit. Below is what I would do.

Option 1 see if you can extend the warranty and keep riding it till that extended warranty runs out then sell it.

Option 2
TRS Valve
Speedwerx V Force 3 reeds for reliability
Speedwerx Sleeper head. I love my SLP head on my 850 NA. Speedwerx claims the sleeper head has better cooling and lighter than any billet head.
Kurts P22 roller bearing delete (auto adjuster elimination) (Patricks might be able to install) This is like getting first gear back in a 10 speed transmission. P22 essentially starts out in second gear compared to the P85 clutch because of the auto adjuster. This will help the sled get going till the turbo kicks in.
Roller bearing delete requires sending secondary to Patricks to have adjuster bolt added back to the secondary. Then rebalance and machine secondary to lighten.
Fire N Ice clutch cover for reduced inertia, better tower support, and a longer bushing to support shifting. Note primary clutch needs to be rebalanced when installing an after market cover send primary to Patricks for rebalance with secondary.
Fire N Ice primary bolt made by ARP (reliability)
Lap primary clutch to crank. (reliability) Ask Patricks to send you some lapping compound.
Carls tri roller torsion clutch kit.
New Polaris pistons (reliability)
New bearings and connecting rods on crank for reliability. Indy specialty could do it. I lost a connecting rod bearing this year on a 2020 850 NA with 2000 miles. Granted I did have some det codes every now and again for a couple seasons till I got it figured out so I am sure that didn't help out. I know polaris has made a few updates to the crank since 2020. But might be something to consider if you are going to keep the sled around a while as a back up / loaner sled.
If you do send your crank to indy specialties to be refreshed you might consider sending the cylinders as well to have them torque plate honed before dropping in new pistons.
I have read the 2025 850 NA's run stronger than previous sleds and the factory "tune" is backwards compatible to 2023. Might ask if the latest factory boost "tune" has any improvements that make it worth reflashing your sled.

 

[doudea]

This is a post I put in an earlier thread. Just copying and pasting. Some thoughts on the factory 9 boost sled:

So I did a true 9R build with the Carl's 900 boost top end on my 24 boost, and also put a BoonDocker intercooler kit with the TRS intake valve. I purchased the Carl's kit from BBA, and Chris flashed it fall of 23 with what I believe was a Polaris development map. Which ran okay that first season i had it, but ultimately wasn't substantially stronger than my previous and other friends 850 boosts. However the lightweight crank and the factory 9R fly wheel were awesome upgrades for the low end response improvement. Side note, the stock 9R flywheel is lighter than the ZRP lightened 850 Boost fly-wheel, I have both and weighted them and 9R is like 18 grams lighter (So not much, but it is the lightest).

So this season it branched out on the tunning aspect and have tried the 24 Carl's 50/50 mapping, and all the different Bikeman 900 maps. Then just this week I got the new updated 25 Carl's pump gas a and 50/50 mapping.

In my humble opinion the Bikeman tunning with the 24 mulit-map 900 flash, and all the 25 single map flashes are all by far the least favorable for me and what I like. Bikeman feels to pull a bunch of timing out of the top end of the mapping which makes the sled feel very lazy to me. I will not spend any more money on Bikeman tunes.

The best of 9 boost tunes for what I like, are the Carl's developed tunes. With this years 2025 Carl's 50/50 map being by far the best. It is based of the stock 25 base mapping from Polaris, which has noticeable improvements to the mid-range power valve strategy.

To further answer the original question, for my 2025 sled I did the 9R crank, and 9R fly-wheel with the stock 850 top end, also with the BoonDocker intercooler & TRS valve. To answer which is better, the 900 Carl's boost top end or the stock 850 both with 9R crank and 9R fly-wheel? My answer is they are both very close, the 900 Carl's has better mid-range grunt and very slightly better top end. Between the two to get the same rpm on the same clutching with the same target boost level, the 900 Carl's is pulling like 2 grams more primary weight. So the ultimate is the 900, but the best bang for the buck in my humble opinion is the 9R crank & 9R fly wheel, with the stock 850 top end. Which saves a fair amount of money by keeping the stock 850 top end.

Last year I ran the 900 with the SLP head that came wit the kit. This year I'm running the Speedwerx high compression heads on both of the sleds. Which both sleds are 165x3.25 Khaos Boosts, so very similar comparisons.

Right now what I'm playing with is turning the target boost level up on the 25 Carl's 900 tune with tuner pro. I’ve tried 1psi and 2psi above the Carl's 50/50 map target boost level, while still running 50/50 91non/100LL. Which with the boost turned up the 9 boost is finally a freaking beast compared to the 850 boost. Better performance through the entire RPM range.

I’m building a fresh Carls 900 ported top end with the 9R crank and 9R fly-wheel, BD intercooler, Speedwerx head, and my modified ecu tune with the boost turned up for next season, to drop in my 2025 sled. Which will be my main ride for next season.

 

[doudea]

This is a post I put in an earlier thread. Just copying and pasting. Some thoughts on the factory 9 boost sled:

So I did a true 9R build with the Carl's 900 boost top end on my 24 boost, and also put a BoonDocker intercooler kit with the TRS intake valve. I purchased the Carl's kit from BBA, and Chris flashed it fall of 23 with what I believe was a Polaris development map. Which ran okay that first season i had it, but ultimately wasn't substantially stronger than my previous and other friends 850 boosts. However the lightweight crank and the factory 9R fly wheel were awesome upgrades for the low end response improvement. Side note, the stock 9R flywheel is lighter than the ZRP lightened 850 Boost fly-wheel, I have both and weighted them and 9R is like 18 grams lighter (So not much, but it is the lightest).

So this season it branched out on the tunning aspect and have tried the 24 Carl's 50/50 mapping, and all the different Bikeman 900 maps. Then just this week I got the new updated 25 Carl's pump gas a and 50/50 mapping.

In my humble opinion the Bikeman tunning with the 24 mulit-map 900 flash, and all the 25 single map flashes are all by far the least favorable for me and what I like. Bikeman feels to pull a bunch of timing out of the top end of the mapping which makes the sled feel very lazy to me. I will not spend any more money on Bikeman tunes.

The best of 9 boost tunes for what I like, are the Carl's developed tunes. With this years 2025 Carl's 50/50 map being by far the best. It is based of the stock 25 base mapping from Polaris, which has noticeable improvements to the mid-range power valve strategy.

To further answer the original question, for my 2025 sled I did the 9R crank, and 9R fly-wheel with the stock 850 top end, also with the BoonDocker intercooler & TRS valve. To answer which is better, the 900 Carl's boost top end or the stock 850 both with 9R crank and 9R fly-wheel? My answer is they are both very close, the 900 Carl's has better mid-range grunt and very slightly better top end. Between the two to get the same rpm on the same clutching with the same target boost level, the 900 Carl's is pulling like 2 grams more primary weight. So the ultimate is the 900, but the best bang for the buck in my humble opinion is the 9R crank & 9R fly wheel, with the stock 850 top end. Which saves a fair amount of money by keeping the stock 850 top end.

Last year I ran the 900 with the SLP head that came wit the kit. This year I'm running the Speedwerx high compression heads on both of the sleds. Which both sleds are 165x3.25 Khaos Boosts, so very similar comparisons.

Right now what I'm playing with is turning the target boost level up on the 25 Carl's 900 tune with tuner pro. I’ve tried 1psi and 2psi above the Carl's 50/50 map target boost level, while still running 50/50 91non/100LL. Which with the boost turned up the 9 boost is finally a freaking beast compared to the 850 boost. Better performance through the entire RPM range.

I’m building a fresh Carls 900 ported top end with the 9R crank and 9R fly-wheel, BD intercooler, Speedwerx head, and my modified ecu tune with the boost turned up for next season, to drop in my 2025 sled. Which will be my main ride for next season.

Attached is my 24 900 boost with the Carls tune and 2 additional psi I added for a target boost setting. This is with the stock airbox, so the BD intercooler is recommended to help keep the charge temps down.

 

[goforbroke]

This is a post I put in an earlier thread. Just copying and pasting. Some thoughts on the factory 9 boost sled:

So I did a true 9R build with the Carl's 900 boost top end on my 24 boost, and also put a BoonDocker intercooler kit with the TRS intake valve. I purchased the Carl's kit from BBA, and Chris flashed it fall of 23 with what I believe was a Polaris development map. Which ran okay that first season i had it, but ultimately wasn't substantially stronger than my previous and other friends 850 boosts. However the lightweight crank and the factory 9R fly wheel were awesome upgrades for the low end response improvement. Side note, the stock 9R flywheel is lighter than the ZRP lightened 850 Boost fly-wheel, I have both and weighted them and 9R is like 18 grams lighter (So not much, but it is the lightest).

So this season it branched out on the tunning aspect and have tried the 24 Carl's 50/50 mapping, and all the different Bikeman 900 maps. Then just this week I got the new updated 25 Carl's pump gas a and 50/50 mapping.

In my humble opinion the Bikeman tunning with the 24 mulit-map 900 flash, and all the 25 single map flashes are all by far the least favorable for me and what I like. Bikeman feels to pull a bunch of timing out of the top end of the mapping which makes the sled feel very lazy to me. I will not spend any more money on Bikeman tunes.

The best of 9 boost tunes for what I like, are the Carl's developed tunes. With this years 2025 Carl's 50/50 map being by far the best. It is based of the stock 25 base mapping from Polaris, which has noticeable improvements to the mid-range power valve strategy.

To further answer the original question, for my 2025 sled I did the 9R crank, and 9R fly-wheel with the stock 850 top end, also with the BoonDocker intercooler & TRS valve. To answer which is better, the 900 Carl's boost top end or the stock 850 both with 9R crank and 9R fly-wheel? My answer is they are both very close, the 900 Carl's has better mid-range grunt and very slightly better top end. Between the two to get the same rpm on the same clutching with the same target boost level, the 900 Carl's is pulling like 2 grams more primary weight. So the ultimate is the 900, but the best bang for the buck in my humble opinion is the 9R crank & 9R fly wheel, with the stock 850 top end. Which saves a fair amount of money by keeping the stock 850 top end.

Last year I ran the 900 with the SLP head that came wit the kit. This year I'm running the Speedwerx high compression heads on both of the sleds. Which both sleds are 165x3.25 Khaos Boosts, so very similar comparisons.

Right now what I'm playing with is turning the target boost level up on the 25 Carl's 900 tune with tuner pro. I’ve tried 1psi and 2psi above the Carl's 50/50 map target boost level, while still running 50/50 91non/100LL. Which with the boost turned up the 9 boost is finally a freaking beast compared to the 850 boost. Better performance through the entire RPM range.

I’m building a fresh Carls 900 ported top end with the 9R crank and 9R fly-wheel, BD intercooler, Speedwerx head, and my modified ecu tune with the boost turned up for next season, to drop in my 2025 sled. Which will be my main ride for next season.

Lots of awesome information. Thank you

 

[FlynHigh]

Attached is my 24 900 boost with the Carls tune and 2 additional psi I added for a target boost setting. This is with the stock airbox, so the BD intercooler is recommended to help keep the charge temps down.

What did you use to data log with? That’s an awesome graph. Good call on the lighter crank and flywheel. Have you ever had Patrick lighten the secondary? Seems like that saves a decent amount of weight but can’t remember how much. It’s rotating mass on the outer part of the sheeve so it should make a decent difference.

 

[polcat96]

What did you use to data log with? That’s an awesome graph. Good call on the lighter crank and flywheel. Have you ever had Patrick lighten the secondary? Seems like that saves a decent amount of weight but can’t remember how much. It’s rotating mass on the outer part of the sheeve so it should make a decent difference.

It looks like an EZ Lynk graph