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Discussion Starter · #1 · (Edited)
I know this subject has been beaten to death. And I know theres some people that swear against it, but watching this video of MCN riding Davies's WSS 675, I couldn't help but notice his forks were below the top of the upper triple clamp as well. Im assuming WSS doesn't allow the changing of triple clamps or they would have swapped them out with different units.

Any thoughts from guys who have tried both stock and this setting who actually race or atleast track ride fairly seriously?

[nomedia="http://www.youtube.com/watch?v=npii7CBb6IU"]YouTube - Triumph Daytona 675 and Street Triple R race bikes ridden[/nomedia]
 

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Alot of it depends on the tires your running, even same tire like the pilotpowers, have different profiles depending on compound and makes a bike differents in ride heigths. also depends on rear shock length, if stock or aftermarket, so many things to account for...
I had mine below the top of the tripple and still turing too fast, had to lower the rear like 5mm, is better but fast, and I came off 3 seasons racing tz's, so i know abit about fast steering inputs...also depends on how much springs in the front, how deep you brake into corners, how loaded you keep the brakes during turn in...
 

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It's called Rake.. The lower the forks sit in the triples the more the trailing rake decreases creating a faster turn in. Raise the triples up and the greater the trailing rake becomes creates a slower turn in and should give more high speed stability.

For Instance if a bike had a 32deg trail rake the turn in would be very quick.
If the same bike had a 45deg trail rake slower turn in with better high speed handling
 

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Trail and rake are two different things. I would think that a trailing rake would be one where the wheel sits behind the pivot point much like the casters on a chair and a proceeding rake would be like on a motorcycle. Rake is the angle at which the forks are in respect to an imaginary vertical line and this does affect trail but trail is affected more by the offset of the triple clamps (i.e. how far ahead or behind the steering head that the forks sit). A steeper rake can make turn in faster but you can have steep rake and a long trail and it would still be slow to turn in but kind of nervous at high speed due to the steep rake. You can also change your rake by raising and lowering the rear of the motorcycle and this is why setting suspension sag is so critical.
 

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Trail and rake are two different things. I would think that a trailing rake would be one where the wheel sits behind the pivot point much like the casters on a chair and a proceeding rake would be like on a motorcycle. Rake is the angle at which the forks are in respect to an imaginary vertical line and this does affect trail but trail is affected more by the offset of the triple clamps (i.e. how far ahead or behind the steering head that the forks sit). A steeper rake can make turn in faster but you can have steep rake and a long trail and it would still be slow to turn in but kind of nervous at high speed due to the steep rake. You can also change your rake by raising and lowering the rear of the motorcycle and this is why setting suspension sag is so critical.
Excellent Point
 

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Tbsgraphics had it right on the tires, and unless I'm mistaken the WSS guys are generally running taller 190/55 rubber on the back. So since they're restricted to stock triple clamps, if BE1 didn't raise the front to compensate they'd be steepening the rake and reducing trail even more than the stock numbers, which are imho lower than they really should be.

I don't think any other current company runs as little trail in the front end as Triumph does on the 675. Makes it easy to initiate a turn, but leaves it a bit short on mid-corner stability and feel. Trail is what makes a bike steer into a corner by itself when you lean it and gives it the self-righting capability. Some bikes you notice that sensation more through the bars more than others, and generally more or less trail is the reason. Ever see those riderless bikes going along by themselves after the rider's fallen off? That's trail at work. More trail gives you more feedback on small lean angle changes, but too much and you're fighting the front end and risking washing the front at high lean. If you don't have enough, the bike will practically steer itself into the ground if you didn't override it. Most bikes run in the low 90's to 100mm of trail, but the 675 is in the low 80's out of the box. Raising the front and/or lowering the rear will get you into the upper 80's but any more would need new triple clamps.

I noticed in one of the 675R reviews that the NIX30 Ohlins that come on them are longer than the normal forks so you can raise the front even more. Shame they didn't throw in some adjustable triple clamps for homologation purposes! :cool:
 

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Tbsgraphics had it right on the tires, and unless I'm mistaken the WSS guys are generally running taller 190/55 rubber on the back. So since they're restricted to stock triple clamps, if BE1 didn't raise the front to compensate they'd be steepening the rake and reducing trail even more than the stock numbers, which are imho lower than they really should be.

I don't think any other current company runs as little trail in the front end as Triumph does on the 675. Makes it easy to initiate a turn, but leaves it a bit short on mid-corner stability and feel. Trail is what makes a bike steer into a corner by itself when you lean it and gives it the self-righting capability. Some bikes you notice that sensation more through the bars more than others, and generally more or less trail is the reason. Ever see those riderless bikes going along by themselves after the rider's fallen off? That's trail at work. More trail gives you more feedback on small lean angle changes, but too much and you're fighting the front end and risking washing the front at high lean. If you don't have enough, the bike will practically steer itself into the ground if you didn't override it. Most bikes run in the low 90's to 100mm of trail, but the 675 is in the low 80's out of the box. Raising the front and/or lowering the rear will get you into the upper 80's but any more would need new triple clamps.

I noticed in one of the 675R reviews that the NIX30 Ohlins that come on them are longer than the normal forks so you can raise the front even more. Shame they didn't throw in some adjustable triple clamps for homologation purposes! :cool:
Everything else is spot on. The 675 needs more trail to be more stable (I found this out the first trackday I did, and have had the triples flush ever since). A few people who know a thing or two about racing these bikes agree with that as well, and unless you're willing to dish out some serious loot for adjustable triples, raising the triples up is the only thing you can do.

I guess I could see where this would very by track, but haven't been to one yet that I've felt sacrificing the stability would be worth the quick turn in.
 

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I actually ride with -1mm on the front fork and +2mm on the rear shock. Don't "chopperize" your Daytona.
Now there's an image, a Daytona with ape hangers and a sissy bar... :laugh:

If you like -1/+2 that's fine of course; different people will like different settings. That's why they're adjustable after all.

But doing that is running against the grain; there's not another SS bike on the market with steering numbers as quick as the Daytona's and there's a reason for that. Every manufacturer is free to engineer the solution they think best, and after years of iterative model changes they've all ended up with higher trail numbers in the front.

That's what's really needed rather than more rake - it's just that with stock triple clamps the only way to get more trail is to increase the rake. Which is why Triumph put longer forks on the 675R. Who knows, ape hangers might be next! :biggrinjester:
 

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Now there's an image, a Daytona with ape hangers and a sissy bar... :laugh:

If you like -1/+2 that's fine of course; different people will like different settings. That's why they're adjustable after all.

But doing that is running against the grain; there's not another SS bike on the market with steering numbers as quick as the Daytona's and there's a reason for that. Every manufacturer is free to engineer the solution they think best, and after years of iterative model changes they've all ended up with higher trail numbers in the front.

That's what's really needed rather than more rake - it's just that with stock triple clamps the only way to get more trail is to increase the rake. Which is why Triumph put longer forks on the 675R. Who knows, ape hangers might be next! :biggrinjester:
Lol
I can tell you that some years ago, i was one of the most "chopper-trail lovers" on the italian Triumph forum; I didn't put on ape hangers, only for the little room under the plexi screen :rofl2:
However, since I realized that the "problem" was not the little trail, but shitting tires (and under-inflated, as the "track way-to-do imposes) and bad suspensions settings, I timidly began to listen to those "stupids" that was all along searching more and more fast-cornering performances.

With good Dunlop tires (i don't know what models of tires are sold in USA), inflated at the correct pressure (fearfully too high for many "wannabe Valentino Rossi" riders), and good suspensions setup (too soft, too cheap and too little Ohlins fashion gold for the same ones), there is no need of increasing trail for decrease bike sensibility; on the contrary, it's possible to achieve an amazing agility without compromises in stability and ride precision.
 

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Discussion Starter · #13 ·
Ive left my forks recessed about 1mm from the surface of the triple clamp and have had good feedback and feel with the bike thus far. Ive also noticed that all of the newer Daytona 675s that come out of the crate have the forks flushed with the triple clamps.

And yes of course taller rear tires will attribute to less trail, however the stock Daytona comes with 89.1mm of trail, so with the forks flushed down it is probably closer to 91mm or so.
 

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Interesting observations, especially the rake/trail numbers; hadn't realized Triumph had already chopperized :biggrinjester: the bikes.

My bad for not keeping up with changes and thinking they were still the same as my '07. I undershot the original numbers a bit in my first post going from memory; they were 23.5/86.8, so it looks like they've tweaked the front/rear ride heights a bit since the triple clamps are the same. Maybe at the '09 model refresh? Dunno; the current front tires may well be a bit taller as well which would add some trail too.

All comes down to personal preference of course. Mine's running in what Warsteiner would think is virtual easy-rider mode. -2cm at the rear with custom [FLUX] link plates and the forks showing 1cm above the clamps for a net 1cm reduction in rear to front ride height bias. You couldn't get that much R/F change with stock forks; maybe with the new Ohlins units on the R you could do it. Works well for me, plus the slight reduction in overall CG lessens the dive/squat tendencies too. Would still love to have a set of Attack adjustable clamps, but seem to have lost that winning lottery ticket I had laying around here... :cool:
 

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I've been running with the forks flush with the triples since Dave Moss set it up about 3 years ago and it felt much better on the track.

I'm going to try a 190 rear once I finish off the tires at my next trackday and will likely take out 2 mm in the rear to compensate.

Anyone else play around with a 190 rear?
 

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I don't think any other current company runs as little trail in the front end as Triumph does on the 675. Makes it easy to initiate a turn, but leaves it a bit short on mid-corner stability and feel.
The 04-05 R6 would like a word with you. Remember those? They had a REALLY seriously twitchy front end.
 

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Would add that the Supersport bike is not a good guide.....

Tires, Linkages, Shock Length and Fork Length ( spacers ) can all be changed
and they all tie together to complete ride height and attitude.



Start diagnosing with what the bike DOES .... then decide if fork height will help that symptom.


Tom
 
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