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Suspension Set Up

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Old 06-30-2009, 05:56 PM
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Suspension Set Up

Looking for some suspension settings to use as a start point. I weigh 93kg or 205lbs and ride reasonably aggressively. Anybody else about my weight with a set up they are happy with. My springs etc are stock.
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Old 06-30-2009, 07:10 PM
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Start with some new springs 0.90kg/mm and a revalve. If you can afford a shock then get one. If not then set your shock preload at 2nd from softest and adjust rebound so it comes up slightly slower than the front.
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Old 06-30-2009, 09:19 PM
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Any suggestions for front with stock springs?
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Old 07-01-2009, 04:12 AM
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At 93 Kg I can safely say that it makes very little difference how you setup the stock front... It's still going to bottom out and go all wobbly... The stock springs are kind of ok for someone in the 45-50 Kg weightclass... And your gonna need one hell of a diet to get there...
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Old 07-01-2009, 05:39 AM
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Hi Banjo3006

I'm new to the VTR forum and some of what I have to say is in all likelihood old news but here goes.
Take Hawkrider and Tweety's advise first off. The stock front end is way under sprung.
With stock springs and valving, I hit a small pot hole while leaned over and the front end bottomed out. It almost bucked me right off the bike and was only holding on with my foot/ankle on edge of seat (very tight spinkster if you know what I mean).
Before starting any mod, take a sag measurement with you on the bike and record it. When you install a new stiffer spring, set the sag to 30mm. Your old measurement will come in handy later when doing other adjustments. I personally run with the front forks raised 10mm in the triples to make up for the increased ride height with new springs and in addition have added a 5mm spacer under the rear shock. I now have an Ohlins shock in the rear and at the track I further increased ride height in the back because the pegs are touching down in tight corners. And no I don't have feelers. The bike has never been twitchy with the overall geometry change.
Next to the front spring and valving change, the Ohlins makes for a huge improvement both on the street and at the track. I do all my own work, however after all the suspension changes, I had a suspension speciallist at one of the track days adjust the front rebound and rear rebound and compression (Ohlins). The $ 45.00 was money well spent and only took him 15 minutes.
After reading all the threads on front end swaps to modern inverted style, I'm hornier than a ten pecker owl to do the change. I'm all ears if anyone knows were I can get one!
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Old 07-01-2009, 03:02 PM
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Originally Posted by banjo3006
Any suggestions for front with stock springs?

You can't really get anything to work correctly with the wrong spring rate for your weight. You'll always have some aspect of the performance that is messed up. Springs aren't that expensive, I can hook you up with a set for $85. I think I might even have a set of used 0.90kg/mm springs. PM me if you are interested.

Valving is also a great idea. Many people will describe how big an improvement they got by going with new springs matched to their weight, and often they stop right there. Springs jujst support the load, the valving is what really makes the bike stick to the ground.
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Old 07-01-2009, 05:17 PM
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Originally Posted by banjo3006
Any suggestions for front with stock springs?
Take it easy in the curvy stuff... That's about it...
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Old 07-01-2009, 09:04 PM
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Was hoping to get away with things the way they were but had a feeling after using the racetech spring calculator I would be up for springs and might as well do the valving at the same time. From what I could tell on the racetech site it looked like the rear was not under sprung so may get away with no mods there other than one of those spacers I've been reading about. How many here have tried a spacer on their vtr.
PS Thanks for the help so far

Last edited by banjo3006; 07-02-2009 at 09:40 PM.
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Old 07-01-2009, 09:06 PM
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Originally Posted by Tweety
Take it easy in the curvy stuff... That's about it...
I know and you know thats just not possible
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Old 07-02-2009, 12:45 AM
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Originally Posted by banjo3006
I know and you know thats just not possible
Well, it is possible... Not very likely though... That's why I ended up starting to modify my bike...

Originally Posted by banjo3006
Was hoping to get away with things the way they were but had a feeling after using the racetech spring calculator I would be up for springs and might as well do the valving at the same time. From what I could tell on the racetech site it looked like the rear was not so under sprung so may get away with no mods there other than one of those spacers I've been reading about. How many here have tried a spacer on their vtr.
PS Thanks for the help so far
Yeah, once you are in there, do the valves at the same time... The cost is negligable in terms of performance... It's the work that's the factor...

Um, no, the rear is not undersprung... And a shim is an easy way to sort out the geometrics... Altough I refuse to call what Honda installed a shock... It could just as easily have been replaced by a 2x4 and you wouldn't know the difference...

I though it was bad until I tried a CBR F4i instead... Then I revised that asessment to horrible... Either get an aftermarket shock of choiche or look here https://www.superhawkforum.com/forum...ad.php?t=17193
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Old 07-02-2009, 04:59 AM
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Originally Posted by banjo3006
Was hoping to get away with things the way they were but had a feeling after using the racetech spring calculator I would be up for springs and might as well do the valving at the same time. From what I could tell on the racetech site it looked like the rear was not so under sprung so may get away with no mods there other than one of those spacers I've been reading about. How many here have tried a spacer on their vtr.
PS Thanks for the help so far
A shim does help. I've run +6mm with the stock shock with good results. I way higher than that now...

As for the rear spring, you would benefit from a higher rate too. The stock spring is correct for a ~165lb rider. I'd suggest something a little higher for your weight. You can revalve the stock shock, the people who I've done that for have really liked the results. You can also put a converted CBR shock on there. Either way there are a lot of options.

If you want to discuss more on the options, shoot me a PM.
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Old 07-02-2009, 06:58 AM
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Originally Posted by Hawkrider
Start with some new springs 0.90kg/mm and a revalve. If you can afford a shock then get one. If not then set your shock preload at 2nd from softest and adjust rebound so it comes up slightly slower than the front.


banjo... hawkrider does a great job rebuilding / custom valving front forks !
well worth the money. after having the correct springs a fork brace will also help.

tim

Last edited by trinc; 07-02-2009 at 07:01 AM.
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Old 07-02-2009, 04:04 PM
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Originally Posted by trinc
banjo... hawkrider does a great job rebuilding / custom valving front forks !
well worth the money. after having the correct springs a fork brace will also help.

tim


I see you edited out your comment about the 0.90's being too soft. The calculation spreadsheet that I use for springs valving comes up with 0.91kg/mm as the theoretical value. That's for a street rider, if the rider is really agressive (or does quite a bit of track time) I'd bump them up to 0.95's but certainly not 1.0's. I'm 215-220lb and I run 0.95kg/m springs.
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