Yup I'm sure Tom and Jay completely agree with you.:face-icon-small-dis. Just like his 872 some people thought that it didn't work . However they thought they were a bad ass tuner. If that was the case they would be selling bad ass motors but guess what they're not what's that tell you. If you do exactly what he tells you to do it will out perform any stock 850 including a properly set up one. If you're not quite the clutching professional that you thought you were mabe you should call a true clutching professional like I- backshift or roosterbuilt.
850 big bores? No talk all season about them?
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Yup I'm sure Tom and Jay completely agree with you.:face-icon-small-dis. Just like his 872 some people thought that it didn't work . However they thought they were a bad ass tuner. If that was the case they would be selling bad ass motors but guess what they're not what's that tell you. If you do exactly what he tells you to do it will out perform any stock 850 including a properly set up one. If you're not quite the clutching professional that you thought you were mabe you should call a true clutching professional like I- backshift or roosterbuilt.
I have decided against the BB and heres y. @ 6-8000ft the turbo is the best bang for the buck and no to minimal modifications to the stock sled.
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Imo an 850 turbo would be the most unreliable sled out there. The engine vibration just wreaks havoc on finnicky mechanical things.
Proceed at own risk.
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I have a well setup 850 with 165, A 927 with 165, and a BD turbo 175, also had a 872 that went in 3 different sleds, 872 was a stellar performer every day, the 927 not so much, the one question I have is Dave states that you need to run his fuel programmer? did the winning sleds listed above have that programmer or did they have the Silber reflash ??? so now on to how these sleds stacked up, 872 w/174 vs 927 with Daves power commander map--10,000 ft Alt 15-20 inches of new snow--- If by chance the 927 would stay out of limp mode and setting check engine lights it still would not run with the 872, the only way the 927 would pull the 872 was to take the programmer off and run stock fueling [and no more lights or limp mode] with a blend of 25%112 to 75% 91 non ethanol, now for the setup 850, base gasket change, timing, clutching and gearing it was always a tossup, so $500.00 vs $2400.00 pretty easy decision, same end result. I wont tell you not to buy one but maybe find one that he claims is a runner and throw a leg over it and find out before you drop the coin, also one other thing to think about is access to replacement parts. you're tied to one small shop in MN.
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I guess there's always a risk when u modify anything. I'm gonna take that chance on low boost and good fuel. See how long it lives.
OMG. Snowbikes, mountain bikes, dirt bikes. Keep educating us about our snowmobicyles. Do you actually ride sleds or just hump a PC all day? Come to McCall, lets go for a rip.
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Hump a PC all day? That is golden. Freakn golden.
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H
Alot of people not liking the BB. Personally, have done all, stock and clutched, full on mod, turbo and BB. The TMS 927 with his latest clutching, perfect for my riding style, playing in the trees and blazing my own trails in places with the occasional hill climb. Anyone stating that "you" will not be happy with a BB is overstating their status of knowledge. Maybe they do not like them and they need a turbo to get them where they are going...come spring time, i jump on a ole 600 to keep it interesting.
If possible, i would throw your leg over what ever you can, not like these toys are cheap, sucks dumping all that money and not liking what you have.
I have been riding for over 30 yrs and this is the best sled i have ever ridden for my style of riding.
If possible, i would throw your leg over what ever you can, not like these toys are cheap, sucks dumping all that money and not liking what you have.
I have been riding for over 30 yrs and this is the best sled i have ever ridden for my style of riding.
R
bb tms 927
i have been runing my trygstad motorsports 927 for two years and it has worked awsome any updates that dave has come out with he has given me. TMS customer support is over the top i have 1600 miles and the sled is working great sled was set up by frank may in utah they are amazing people cant wait for the snow to come
i have been runing my trygstad motorsports 927 for two years and it has worked awsome any updates that dave has come out with he has given me. TMS customer support is over the top i have 1600 miles and the sled is working great sled was set up by frank may in utah they are amazing people cant wait for the snow to come
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J
Lol.
I guess you could say I do "hump" a PC a lot of the time. Its very well known I help out with a number of different companies in the sled world as a consultant in web/media/marketing roles. I'm good at this sort of thing and it's offered me a lot of opportunity in the sled world.
I also am a photographer, often riding with real pros (not snowest pros) such as aforementioned Jay and Blaine. My full name is Jeff Brines, go ahead and ask around about me. I'm not hiding behind an internet handle and welcome constructive feedback.
I often do borrow from other sports, I think there is a lot to be learned, especially when we are talking about something so esoteric and small as mountain snowmobile riding. Learning from other sports is an excellent way to move the ball forward and not reinvent the wheel.
The math is super simple with the big bore stuff. It can absolutely work, but its not going to put down a whole lot of power. Depends what you are looking for, of course.
As far as Dave's external box vs reflash goes, I am bias obviously, but I am positive Jay/Blaine were running Silber's maps on their sleds...in fact, those maps were built for a reason. Let you guys do the math there.
TMS 927
Thanks for the straight up review on the TMS927 that Brent installed for you,
No one better than him to do the work and make sure everything is installed and done correctly.
More updates in the works to make them even better!!
Dave Trygstad
Thanks for the straight up review on the TMS927 that Brent installed for you,
No one better than him to do the work and make sure everything is installed and done correctly.
More updates in the works to make them even better!!
Dave Trygstad
Jeff
You must have a long backround in the 2 cycle engine development business especially the Rotax G4-850 being made into a Bigger bore. Guessing you and your team has had a chance to dyno one in your product design facility up north in Minnesota?
Watching the RMSHA final results at the end of the season I see that the TMS 927 had better postings with the same riders than they did on the Silber Turbos that you sponsored.
Interesting to see you continue to post comments against my line of products and promote yours when someone starts a thread asking about G4 Big bores.
Leaves lots of options open for us at TMS in the future.
Maybe give a call sometime and we can chat current engines mainly the 850-927 with or without a Turbo.
J
First and foremost, this is a forum (which means its a place to discuss ideas). I also mentioned my brand affiliations and roles with various companies out of complete transparency.
The thread title was pertaining to why there are not more big bores. I don't feel I'm overstepping any boundaries giving my opinion (again, its a forum) as to why we don't see more big bores these days. The math is pretty simple, both economically and considering how a BB makes its additional power. The physics are what they are and unless you can defy them somehow, the output math is also very straightforward (again, unless you have some unicorn magic we don't know about).
People mentioned your product in t his thread, and that's great (but it doesn't give you ownership over the thread)! I know Jay and Blaine love it! I also know we built a proprietary map that we offer for sale to anyone looking to increase the ease of running the 927 as tuning leaves something on the table. With the reflash, it is as turnkey as it could possibly be while offering a hair more performance. (Jay ran this map at Jackson)
...all that said, a perfectly tuned big bore is not going to dangle with a low boost (5psi plus) turbo in the mountains when it comes to output. Some riders love a N/A sled in terms of its power band. Nothing wrong with that at all, and for those looking for a few extra horsepower with deep pockets, your product is a viable option!
Turbos (across the board) are far easier to run than even a handful of years ago, the cost significantly down, technology proven and install is easy (and easy to go back to stock if you chose). Hard to say the same about a Big Bores. 10 years ago turbos cost twice as much as they do now, were tougher to tune/clutch for and that left a very viable market for big bores. These days, its more of a niche product and that's why I answered the thread as I did.
As far as race results, I'm not sure what you are referring to. Wasn't aware Improved and Mod ran together? Fairly certain Jay put down 2nd (or 3rd?) fastest time up the hill on his turbo sled, not BB.
Either way, I hope I answered the poster's question. I am happy to elaborate on the output math if anyone wants...
G4-850 - 927
Possibly and we will add a damper to one soon on the SuperFlow and find our results, One thing to note with the TMS 927 we have worked with piston weights and piston designs to make the 927 engine silky smooth and it spools up quicker than the standard bore 850 even with the added weight in the clutch arm department.
Any drive clutch can be run on this engine package as vibration is basically gone,
Great question!
Dave T.
Possibly and we will add a damper to one soon on the SuperFlow and find our results, One thing to note with the TMS 927 we have worked with piston weights and piston designs to make the 927 engine silky smooth and it spools up quicker than the standard bore 850 even with the added weight in the clutch arm department.
Any drive clutch can be run on this engine package as vibration is basically gone,
Great question!
Dave T.
TMS 927
Opinions are great, FYI it is Tom and Jay running our 927 in the 1000 improved class and doing a lot of winning and Jay even won the points championship in that class, I stated that they did not produce as many top finishes in the mod classes with your 200 hp turbos, same quality drivers in each class.
Reflash is an option for some but it is easy to jack up timing points and build a little more power on anything. No way to offset fuel to each cylinder to help cure the design properties with the 850 platform engine which it needs. We have replaced cylinders for turbo customers and it always the same cylinder with the problem.
Warranty for myself and our customer base is very important as when ECU is flashed it leaves a marker which equates to no more warranty, Race vehicles are differant application as they have no warranty to begin with.
Give a call some evening and I would be glad to discuss what I have seen with the current turbos on the 850's from the past two seasons.
Dave Trygstad
Opinions are great, FYI it is Tom and Jay running our 927 in the 1000 improved class and doing a lot of winning and Jay even won the points championship in that class, I stated that they did not produce as many top finishes in the mod classes with your 200 hp turbos, same quality drivers in each class.
Reflash is an option for some but it is easy to jack up timing points and build a little more power on anything. No way to offset fuel to each cylinder to help cure the design properties with the 850 platform engine which it needs. We have replaced cylinders for turbo customers and it always the same cylinder with the problem.
Warranty for myself and our customer base is very important as when ECU is flashed it leaves a marker which equates to no more warranty, Race vehicles are differant application as they have no warranty to begin with.
Give a call some evening and I would be glad to discuss what I have seen with the current turbos on the 850's from the past two seasons.
Dave Trygstad
J
1) You aren't correct about the ECU reflash leaving a "marker". Obviously if you don't reflash to stock, its easy to tell its got a tune on it, much in the same way if you leave your big bored motor in the sled its pretty obvious its not stock :face-icon-small-win. However, if flashed back to stock there is no "marker". I'm guessing you aren't overly familiar with how the flash process works (we build the code in house...)
2) Warranty with any aftermarket product is out the window. So I'm not sure what you are discussing here. Yes, one could put something back to stock if they want and try to get warranty work...but pulling off a big bore kit off, pulling a box off, seems a pile of work compared to plugging a cable in and pressing a button.
3) Comparing your results in one class to results in another class is apples to oranges. Silly to even do so. Not all riders ride the same classes, and its an entirely different set of rules. Like comparing Touring to Grand Touring cars...or 250F (125cc) to 450F (250cc) Not to mention most people don't buy product to go RMSHA racing, they go to ride in the mountains in deep snow...
4) Sorry on the name screw up - edited for clarity!
5) Please explain how your big bore setups or the 850 requires additional fuel management beyond the capability of the ECU?! You are suggesting Ski-Doo missed something in their design of the control unit, which is a very big claim, especially considering how evolved that control unit is. The amount of air entering the manifold will be consistent across the throttle bodies, hence, the amount of air entering each cylinder will be consistent. This means the amount of fuel per cylinder is also....consistent! On the exhaust side we have a single pipe, so EGTs will be representative of an average of both cylinders. Point is, how can you tell one side is lean, or one side is rich due to air intake inconsistency as you are suggesting? There simply isn't data to suggest this (inconsistent volume of *air* cyl/cyl)
What we've seen is injectors fail (become inconsistent), this was a common problem with the 2018s, which could in theory be "fixed" with a power commander. That said, its a failure of an injector being fixed with a band-aid, not an actual fix (actual fix = new injector or fix whatever is causing the injector to be inconsistent). This was common on mod sleds AND stock sleds. (again, mostly a 2018 problem, but 2017s had it as well). Oh, and when an injector goes, it will throw a code part of the time. Again, stockers have this exact same problem - it has nothing to do with a mod.
Finally you suggesting its easy for us to "jack up timing points" is confusing. Its no harder than building a N/A map in general, we are just doing it around a big bore design using more advanced electronics. (the stock ECU is incredibly powerful)
Put another way, the stock ECU has more capability than any aftermarket tuner box. The exception to this being a complete aftermarket ECU, which in theory could be far more advanced than anything...but would be an incredible amount of work to program.
EDIT: I just want to be *really* clear there is nothing wrong with the 927! My tone is a bit more negative than I intend, maybe because I see the reflash being an awesome way to control fuel for any motor mod. Anyone who wants a big bore, give the 927 a hard look!
S
.The sad thing about this post is a member of this forum has stated that it is the most expensive paper weight that he has, TMS fuel control, TMS clutching, yet no response to help clear up the issue that this and other costumers have had for there $ spent.
J
Just to reiterate, Justin has a flash he's been selling. It 100% does work and will run more reliably than the any tuner box map. It was developed to fix a problem many riders brought to him, including one of his racers.
I'd throw this flash on the sled and make sure everything is installed properly. I'm guessing the TMS clutching is pretty good. (no idea)
I know, nobody wants to throw $500 at something that is already so expensive, but it will work and will at least keep the kit from being a hefty paperweight!
Just an idea for those struggling.
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