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Discussion Starter #1
Ok, now as most of you that are on here are aware, I am relatively new and bought my ST within the past couple of months..... I have been diligently breaking it in and gradually attempting to go 'faster more often' as I get used to it and it breaks in; I have read all these comments about how well these bikes handle and clearly that is NOT the case here, so...

I have a serious handling issue that is precluding my complete enjoyment of the bike (now is a good time to grab a drink before continuing....) and welcome any useful advice or pointers any of you seasoned riders can offer as the dealership whilst being helpful in attitude is dismissive / appears clueless about this issue despite several enquiries and comments being sent their way when I am visiting them, so here goes....

I realize it is difficult for you to judge based upon my feelings or feedback, but that is all we have to go on, so.... ;)

Once I get over 50 mph or so things being to feel 'unstable' (I am thinking this is coming from the front) and this rapidly gets worse by 65 - 70mph making it a real challenge to ride the bike, especially without a need to change underpants.... Any turbulence from other vehicles or going on the freeway magnifies this effect...

On an empty road with NO wind I can go faster without issues, but we all know how rare that is and once some road surface issues or turbulence / wind gets into the equation, things get SERIOUSLY out of hand.

It feels REALLY unstable, as though the front wheel is moving about / shimmering around / squirming around / tire is flat kind of thing

I have ridden MUCH faster on other bikes without ever experiencing this issue and I need to resolve this problem as it is destroying my otherwise unblemished love affair with my Sprint...

I am a 6' 250lb guy who normally rides with the panniers on at the weekend and off during the week (lightly loaded with specs)....

I have tried the following with various results:

I have adjusted the fork preload all over the place from the stock 10mm (measured with a vernier to the top of the fork nut) down to about 6mm - I currently have it around 9mm as that seems to work best for tar strips and other assorted road surface hazards.

As a side not, I have chips / grooves in the top of my left fork fork guard which came lose a couple of weeks ago.

I have turned the rear suspension preload up five clicks from standard to allow for my additional weight.

I have checked both tire pressures with both a digital gauge I bought for the bike and the analogue one for my truck (who read within .5lb of each other) and set the tires to 36 / 40 as per the handbook (they were at 34 / 36 when checked), this did improve things at lower speeds for sure, but....

I have 'wiggled' and compressed the forks many times / checked for 'something loose' and everything is ok so far as I can tell....

I changed out the standard wideshield for an MRA one with a 'spoiler' on the top as I was getting a LOT of buffeting with the standard one.

I use a Joe Rocket carbon fibre full face helmet.

Now, I know I do not have much recent experience, but I am no NOOB to bikes, I have ridden MANY tens of thousands of miles in all weathers on and off road in the UK on various bikes / types of bikes over the years as well as being an ardent mountain biker for years, so please don't assume this is idiotitis.

ANY advice, help, suggestions welcomed as I have run out of ideas myself and I am getting desperate as I love my bike, but I can't live with not going over 55 / these issues!

Thanks, John.
 

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JR,

Sounds like a lose head bearing; did you by the bike new or used?

Put the bike on center stand and get someone of 100 plus pounds to sit on the rear seat. Grab the forks and see if there is any play in the head bearings.

Also I recommend setting the sag per any of the online recommendations.

There has been an issue with some front tires creating a wobble right at about 50. I had this issue with Avon ST tires but it was only noticeable with my hands of the bars and it never really bothered me.
 

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Discussion Starter #3
Appreciate the feeback 3Banger...

I bought the bike new and it has the stock Bridgestones on it.

I will try and round up some ballast tomorrow and try what you suggest. :)
 

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HI JR-Something sounds seriously wrong if you are having that much trouble. I would try another dealer. You don't say how many miles you have on the bike or at what mileage it started.

I'm not a mechanic but I would check(have checked) the wheel bearings, head bearings, check to make sure the forks are aligned.

The stock Bridgestones will cup in the front as they wear and cause some problems. Good replacement tires work wonders to cure those problems. As far as the tire pressure, I always run 34 frt and 36 rear.

I think the Sprint is very stable at speed so you should have a competent dealer help you out.
 

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John,
could you please tell me what tyres you have on and what mileage have they done and how are they wearing.

We will discuss pressures at another time but for now the manual tyre pressures are for MAX load.

As guide I use 32 - 33 solo in the front and 36psi rear this is with Pilot Powers.

I am 220+lbs.

This can be sorted it is only one of a number of things that can cause this, so do not despair it is a process of elimination.

Cheers,
DaveM:cool:
 

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Welcome John, it does indeed seem like something is wrong. The Sprint normally handles very well.

Glad you checked your tyre pressures. I would have done that first too.

Many have commented that the Bridgestone front tyres fitted to the Sprint can make the steering a progressively flappy after they are worn a bit ie. after a few thousand km.

Next you should set the static sags on your front and rear suspension. I like to set mine around 35mm each end. Sag is the fully decompressed length of the suspension less the length of the travel compressed under your weight. There are a few websites around that describe how to do this. The Ohlins website is worth a look. It is better to apply a scientific approach rather than stuffing around willy nilly with the preload screws.

If you are experiencing bottoming out on a regular basis you will need to fit stiffer springs. If I were your weight I would look at fitting 1.05kg/mm springs on the forks and a 1000 lb/in spring on the rear.

Then adjust the rebound damping on the rear shock, the screw is at the bottom of the shock on the left hand side despite what the manual says. This will impact on the amount of wallowing you get after hitting a bump. Choose a setting close to that recommended for 2 up riding in the manual.

Other things to look at are chain adjustment, if it is too tight the suspension will not have freedom to move where it wants. Also fork alignment, axle bolt torque and headstem bearing adjustment can impact on front end stability.

Good luck trying to sort this out.
 

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Discussion Starter #7
Appreciate all the help so far gents, here is some more info. in request to your questions...

The bike now has just over 1000 miles on it from new, it had zero when I started.

Tire wear appears 'normal' so far as I can tell - a dirty smooth strip down the middle of the rear, a kind of 'scuffed' appearance down the edges of the middle of the front, smooth in the center section, very little wear on the sides as I have yet to get into many twisties.

Tire type is BT020.

This issue did NOT appear to be there during the initial ride home, when I rode on the freeway in all the traffic without a problem.

I suspect it is getting progressively worse and my various tweaks are offsetting that mostly which has got us to where we currently are....
 

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If I may make some suggestions in all candor and friendliness.

#1. Stop chasing your tail around and arbitrarily making changes. ( this is what it sounds like)

#2. Since you are getting set up for it check the headstock for play. Be advised that most people over-tighten causing more problems.

#3. Go back to the rear and turn the rear pre-load screw all the way in counting the CLICKS. Then back out about 10-12 CLICKS.
Remember, CLICKS, not turns.

FYI, a lot of what feels like front end weirdness can be attributed to the rear.

Your TP might be a little off. Try 34/36 or 36/38.

#4. Before doing anything else read this and do it.


http://www.racetech.com/articles/SuspensionAndSprings.htm

Only then will you have a baseline to work with and only then can you analyze what's going on.

FWIW to me it just sounds like things are just out of balance between the front and rear.

Do this first and then get back to us.

Don
 

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Discussion Starter #9
Appreciate the suggestions Don - and the link. I don't have a team avail at the mo for the measurement part; but I will get with the clicks n things in the AM and report back.

My adjustments to date are probably not quite as random as they might appear - but are not exactly scientific either! ;) so I think a 'get back to originals and work from there' is an excellent suggestion. :)
 

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A simple way to check the head bearings (if they are on the loose side) is to stand beside the bike and roll it forward a bit, then apply the front brake, any clicking noise or movement felt through the bars will indicate 'loose' head stock bearings.

As for the rest, everyone else is pointing you in the right direction, process of elimination.

Cheers, G :D
 

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All very good advice. Especially Don's to return to a baseline and then do one thing at a time, and make notes. If an adjustment has no effect, return it to the previous position and try another.

One item that has not been mentioned is that the front spacers are different lengths, left to right. Although you would think if this were the case, it would have been noticeable early on. I can't remember exactly which goes to which side, but maybe someone would look at their bike and report back. I would do it, but mine have been cut down.

Memory tells me the left spacer has 2 grooves, while the right spacer has 1 groove. But, do not depend on my memory....I sure don't. :D

If the headstock bearings are loose, you might want to consider having your dealer re-lube the bearings before adjusting the free-play. I know of several that were inadequately lubed from the factory.
 

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Be advised that there has been a recall on the 08's drag link bolts.

(cut and pasted from another source)
Triumph has announced that they will be recalling certain models of the 2008 Sprint ST Motorcycles. They stated that there is a possibility that the single bolt that is used in the 3 positions on the rear suspension drag link assembly can become brittle and fracture. The bolts are involved are the (1) drag link to drop link bolt, (2) drag link to frame bolt, and (3) drop link to rear suspensions unit bolt.

The head of the bolt may detatch causing the drag link assembly to come apart resulting in loss of rear suspension, increasing the risk of a crash. Dealers will remove and discard the 3 bolts and replace them with new bolts. The recall is expected to begin during November 2008. Owners may contact Triumph at 1-678-539-8782.
(end paste)

You may want to find out if yours is one of those on the recall list. It may not be or fix your problem but I would have them checked.

Speed Safe,
Don
 

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Don is right on with his comments.

When you get it sorted, ditch the BT 020's as soon as possible as there are better tyres to suit your Sprint, refer the Tyre sticky in Maintenance tips etc subforum at the top of the forum main page.

DaveM:cool:
 

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Hmmm....... you say the bike is almost new? Isn't this something your dealer should be sorting out under warranty?
 

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FYI, a lot of what feels like front end weirdness can be attributed to the rear.
+1. I've had that experience in the past but not, I hasten to add, on the Sprint.

5 extra clicks on the rear preload seems an awful lot! Why not increase it just one click at a time & see how it feels? It's very easy to adjust with the screwdriver included in the bike's toolkit.

Any significant increase in rear preload should surely be matched with a proportionate increase in the rebound damping otherwise yer sickle's going to pogo over bumps. The damper adjustment scew can be adjusted with the same screwdriver. Pls note that the adjuster screw is on the right hand side of the base of the shock, not the lhs as stated in the manual.

This bike should run stably & as straight as a dye over bumps, in cross winds, with or without panniers, at speeds well in excess of 120mph even on the original BT020's.

DaveB.
 

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+1 on DaveB's rebound damper adjustment.
I've got mine tweaked to the last 1/16th of a turn and it's perfect.
You can adjust your preload all you want, but if your bouncing all over, you'll get the unstable effect you describe.
The fact that you did not feel this when new may indicate that the shock has finally loosened up after it's break-in period (+-1000mi).
I can't help you much without riding your bike, but I can reassure you that the Sprint is solid as a rock on the highway, with crosswinds and rain grooves.
The BT020's should be changed to Avon Storms after 3000 miles.
You made a great choice buying the Sprint, don't let the dealer's ignorance let you down. My bike improved tremendously when I stopped relying on the dealer after the two-year warranty period was over.
Regarding front wheel spacers, ensure that the rotors are equal distance from the inside of the fork.
 

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I've looked through my notes since posting re the wheel spacers last night and see where they are .990 inch and .910 inch respectively. I do not know if that was from my measurements or if I originally got it from another source.

Anyway, the .08 in. difference should be easy to visually detect by sighting over the front of the rotors to see if they are centered on the caliper split lines.
 

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I think everyones suggestions just demonstrates the range of things that MAY be causing this ride experience. It may not be any of these things. Then again some changes effected could improve the ride by way of masking the real problem but offering a improved performance. In the meantime here is a brand new bike that should be performing off the shop floor & it's not. Surely the shop has ridden it - are you telling us they reckon it rides without the issues you have raised. Ride yours then their demo bike over the same route. I'd be finding an independent assessor to ride & 'certify' the handling issues & then get Triumph to either fix it or replace the bike.

If anyone wants to be in the position of trouble shooting a ride then buy a second hand bike but a new bike ....no way. The more you mess with the bike the higher the odds you will void your warranty.
 

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Discussion Starter #19 (Edited)
Again, appreciate everything so far... and yes, I AM a bit pissed I am having to do this with a new bike, but....

In answer to your clicks question Dave, the manual says it is set at '25 clicks', 29 is for soft one up, 21 is for firm one up, set to 15 with rider and luggage, or 05 for fully loaded.... So I decided that being as "I am a fairly big boy' and use luggage, I would begin with an minus 5 and 'see what happened' I did not adjust the rebound thing as I could not find it - I now KNOW why courtesy of you - it is on the other side!

Just to clarify a little more for some as I realize the help you can offer is only as good as the info I provide....

I have only made one adjustment at a time and then ridden the bike (including waiting a day and riding again to try and overcome 'perception issues)....

I have mentioned it at the Dealer each time I go in (they have adjusted the front preload 'firmer' for me twice now in an attempt to help), but I believe their test run (they are downtown) does not include any freeway / 'high speed' work - and the bike is great at lower speeds, so...

They did already change those bolts out - thinking about it, I believe that is when this all started....

I believe there has been a gradual progression in the issue as the miles have been put on the bike and that 'all the adjusting' has changed things a little here or there, but the underlying problem has persisted.

Dave: I did only boost the tires up yesterday and whilst I know you are going to shoot me for this, the bike does feel less 'wallowy' now....

One other clue for those still interested... A couple of times this week when I have crossed over a 'asphalt high ridge' in the road near my home at about 20mph it has felt like the bike is disconnected in the middle / has a hinge in the middle as though the wheels moved independently (if that makes sense).

Heading out to the garage now to 'get back to basics' ;)

Thanks again for the help and advice guys! :)
 

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Any 'issue' that perceptibility started after I had had work done at a dealer (the recall for instance) would leave me feeling very nevous.

If you know of anyone remotely close with a bike, have him (or her) give yours a little ride, not that that might make any difference - but anything really noticeable would be confirmed by a second rider I'm sure.

Although my bike had the recall done, they did not replace the bolt/s but simply re-greased them and reapplied them with their respective clips and washers, failure to have done this correctly, may be the cause of some of your issues.

You are the best judge of what feels right and if doesn't feel right, go back until the dealer sorts it out.
 
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