Gen5 turbo clutching setups /information

[caper11]

Are we talking about engine response or track response? Two totally different things. I try to give an example what I mean.

Let say you are runninng 38mm pivot, cliker #4 and engine runs 8000-8100, thats great. You get that instant pull and rpm is consistent troughout the pull.

And your brother has 33mm pivot, cliker #2 and his engine runs also 8000-8100. His engine response is quicker. He probably gets some overshoot around 8200 in the beginning but longer the pull goes it drops to 8000-8100 which is fine too.

I would say you both have same sled but different qualities. It comes to personal preference, how and where you like to ride. For long pulls, drag racing, more open areas yours is better. For tricks, treeriding, etc. your brothers setup suits better.

BUT

if situation is that you both run 38mm pivot, yours is on #3 and his on #2. Probably whats happening is that your sled has consistent rpm 8000-81000 from the beginning, but your brothers sled has same rpm in the beginning but along the pull it drops to 7900. In this situation you can feel that your sled engages harder and pulls better. This is the reason I allways advice people to match pivot&spring to a desired cliker #.

I’m in a lower clicker, I’m on three in the factory position for the 761, he was on clicker 4, you have it backwards.
The third person in our group riding in the trees with us commented on how much my sled roosts with throttle blips compared to my brothers sled.

So to answer your first question, My throttle is connected to my track, and my sled is very snappy. Maybe you have not picked up on this, but My G5 does not have the factory clutching in it, it was the first thing to go. The only thing being used in my sled is the factory 761 ramps.

Again, My sled has way more mass in the pivot, lower engagement, lower clicker position than my brother’s stock G5, and we are both running the stock 761’s. We let the third person ride both our sleds back to back and he commented how responsive mine was over my brothers.


Sent from my iPad using Tapatalk

 

[Driver]

So you have harder primary spring than stock and also more pivot weight? In that case they kinda rule each other out mostly.

I was on BC last season and stock calibration on turbo was horrible. Engagment was around 4500. And it was running very light alltogether. If thats what high altitude calibration is its no wonder people complain and buy kits there.

 

[caper11]

So you have harder primary spring than stock and also more pivot weight? In that case they kinda rule each other out mostly.

I was on BC last season and stock calibration on turbo was horrible. Engagment was around 4500. And it was running very light alltogether. If thats what high altitude calibration is its no wonder people complain and buy kits there.

I have less start force and lower finish on my spring.
The factory summit spring is a 170-350


Sent from my iPad using Tapatalk

 

[mn.nytronut]

So does the high engagement have anything to do with mitigating turbo lag like a stall converter? Pre spool the turbo....

 

[joshkoltes]

You guys are missing something. Most of us don't ride the same mountain ranges every time.
I live in the horns and tune for here on clicker 3, 8-10000 ft. so when I got top of the world, 9-12000 I can click. And when I go to alpine, 6-8000 I can click.
You shouldn't tune it in at either side of the spectrum unless you don't plan on changing locations.
Which bring me to the stupid magnet weights, can we just stop that crap! Haha

 

[jcjc1]

So does the high engagement have anything to do with mitigating turbo lag like a stall converter? Pre spool the turbo....

highly doubt it. every summit I’ve been on to include non turbos has that crazy high engagement.

 

[rockinmranch]

Are we talking about engine response or track response? Two totally different things. I try to give an example what I mean.

Let say you are runninng 38mm pivot, cliker #4 and engine runs 8000-8100, thats great. You get that instant pull and rpm is consistent troughout the pull.

And your brother has 33mm pivot, cliker #2 and his engine runs also 8000-8100. His engine response is quicker. He probably gets some overshoot around 8200 in the beginning but longer the pull goes it drops to 8000-8100 which is fine too.

I would say you both have same sled but different qualities. It comes to personal preference, how and where you like to ride. For long pulls, drag racing, more open areas yours is better. For tricks, treeriding, etc. your brothers setup suits better.

BUT

if situation is that you both run 38mm pivot, yours is on #3 and his on #2. Probably whats happening is that your sled has consistent rpm 8000-81000 from the beginning, but your brothers sled has same rpm in the beginning but along the pull it drops to 7900. In this situation you can feel that your sled engages harder and pulls better. This is the reason I allways advice people to match pivot&spring to a desired cliker #.

Why are you shootings for 8000-8100. Most dyno charts show peak 7700-7800. Most on this forum also seem to like over 8000. Just curious who has experimented with 7800 and 7900? More weight should pull harder, in theory.

 

[Dynamo^Joe]

Here are two vids of a clutch kit [mine] using too low of engagement [2900] and too much load on the pivot bolt weight. Has slow throttle response and heavy throttle feeling. Its difficult to tree ride, feels like it pulls but you can plainly see, the vehicles aren’t going very fast. They're slow to rev back up and does not feel light. Every tree is a magnet, both guys are working hard trying to muscle the sled, the sleds aren't agile. When you hear the whirl of the track, sounds like "wah waah...", no better than stock.

Hmm... I wonder if the paper mill will let me have my old vibration job back.



and

 

[Driver]

Why are you shootings for 8000-8100. Most dyno charts show peak 7700-7800. Most on this forum also seem to like over 8000. Just curious who has experimented with 7800 and 7900? More weight should pull harder, in theory.

First you need to remember, rpm gauge isnt actually that accurate and reacts slow. It shows RPM in simplified easy-to-read form for consumers and everyday riders.

Im very aware of the dyno results. But theory and real life dont allways come together as you would ecxpect. All the testing and comparing gives us the same results, these sleds run best around 7900-8100. Same goes for naturally aspirated engines. Also belt life is better.

You can add pivot weight, change softer primary spring, steeper cam, whatever to push down rpm to 7700-7800. But truth is that even if sled feels its pulling stronger, its actually slower (with stock gearing). You will also loose throttle response which makes technical riding more difficult.

If you want to win drag races, which seems to be priority for some, first you should go for longer gearing and then workh with primary and secondary. These modern sleds have very slow gearing though we have more power and torque than ever:

2017 850 summit 154": 19-45 -> 2,36
2023 850 summit turbo R 154": 21-53 -> 2,52

Why so short gearing on modern sleds? I dont think there is a simple answer. Belt life problems between 2017-2019 had probably something to do with this, as they wanted to take some load of the belt. But also the way people ride these days. People watch a lot riders like Keskerke and want to do same kind of maneuvers, and then short gearing gives you that snappy response needed. Overall people are riding more and more technical, deeper and steeper stuff. Old school pin and shoot and long speedy wheelies aint a thing no more. On the downside of gearing down, clutching is harder than before and we see a lot more overshooting and RPM drifting, especially when conditions are lighter.

 

[Dynamo^Joe]

The digital tach reacts quick enough, the operator can't read the numbers.
When the XP chassis come out, BRP stated it made an accurate digital tach down to 10 rpms. [BRP update manual softcover paperback] The microcontroller has an algorithm used to calculate the engine speed based on a prediction of constant and rpm rise.
AND...there was a feature in the early XP tachs 2009 where the mechanic could make a 10 rpm sample, a 50 rpm sample and 100 rpm sample rate. The BRP digital tach is not more than 10 rpm out. What the display shows is based on the sample rate settings.

@d)Im very aware of the dyno results. But theory and real life dont allways come together as you would ecxpect.
Joe) "Use" the practice of what you're doing with the engine [the act of how you're consuming the power] measured against the results you want, does not always match what you expect.

I clutched a Drakart Buggy in the UK that runs a lemans type course, long full throttle pulls. The engine on the dyno showed 134hp at 8200 rpms. But always, always always, the fastest top speeds was at 7910~7950 rpms. Run at 8200, lower top speed. Lug the engine above 7900, 90+mph.

Now, shorten the track distance up from this tree to that tree, climbing a hill in Griffin in Revelstoke. I think you'll have a harder pull at 80~8100 than 79~7800 [on an engine rated 7900 +/- 100]

" I would not load Pivot bolt too much. Rather would go to a spring with lower end force. You get the same result or better. "
"You can add pivot weight, change softer primary spring, steeper cam, whatever to push down rpm to 7700-7800"

...that's a recipe. [...formula or procedure to attain something.]
The strictness of maintaining that practice [recipe], you can't get away with that all the time.
Yer telling people to do "something" by repetition without telling them there is effort in measuring your own results to comprehend the settings.

You could be in a situation where you put in a steeper cam, having what you think is correct rpms, but buddy over here went to a shallower cam [one you would never think of using] and has better results according to "your standards", yet with the rpms being off power peak [high or low]?

I can present that scenario because ive seen it in testing, personal firsthand knowledge. Furthermore, you dont know what buddy is setting his clutch at. You ask him after, and he said "i used a steeper helix than you", but he really did the opposite of what you did and what he said.

...now what?

 

[Driver]

When doing clutching its impossible to find perfect setup for every condition and every rider. But its possible to find good compromise to meet riders needs for most of the riding season.

 

[damx]

Got a slightly used 2 rides, sled head racing gen5 turbo kit for sale in canada. $350 cnd. Shipped.

 

[jdog1]

Got a slightly used belt to go along with it!! Haha