Trying to keep the 640 low fender...

[Renazco]

Originally Posted by sherpa

Hey... does anybody have a low fender they want to donate to science...or sell real cheap .

I have a low fender if you need it, It's been experimented on already but should suffice for your lab work. It's your if you want it just pay shipping..

[AntWare]

I noticed the new 990's have a slightly raised front fender so it looks like KTM has addressed this problem somehow. At first glance it looks like it mounts up the same.
Maybe one of the lads over in U'rup could confirm it.

IIRC, they've gone to two independent brake lines as well.
One problem with raising the stock mudguard is the crossover line.

[meat popsicle]

Is there some way to restrict fork travel internally? Sorry, I am not a fork guru by any means, but it seems reasonable to think that one could add some spacers to shorten the travel before the (whatchamacallit) "fork stop"?

Just thinking out loud...

[sherpa]

Originally Posted by boejangles

I have a low fender if you need it, It's been experimented on already but should suffice for your lab work. It's your if you want it just pay shipping..

Sounds great...I can PayPal you some money anytime your ready...just let me know.




Here's my thinking about the low/high guard issues at present...subject to change at anytime though.

The low guard works better at keeping shit off me and the bike.
The low guard MAY allow more airflow and thus better cooling.
The low guard can become clogged with sticky mud causing front wheel lockup.
When you do get the front clogged with mud, the cross over brake line makes removing the guard a PITA.
The low guard can bottom out on the lower triple clamp under full compression...although the guard is a very flimsy thing which wont harm anything by hitting the lower triple.

So...I might try the mods below for awhile prior to converting to the high guard.

Raise the low guard by 5/8" giving me a total of 1 1/2" of clearance to the tire. That's with the supplied Sahara 3's... will probably be less with knobbies.
Replace the cross over brake line with a second line direct from the master cylinder.
Modify the black,plastic, brake line guide that now sits below the lower triple clamp. I'll need a second one of these on the right side for the second brake line. This thing is held on by four bolts...overkill...I'll cut away the center section leaving me with one per side with each held on by 2 bolts...this will give me another 1/4" of clearance before things go BANG.

The only thing that gives me concern about keeping the low guard...is the issue of The Perfect Rock... getting caught in there and causing the front wheel to quickly lockup unexpectedly...resulting in me taking a little flight over the bars. Has this actually happened to anyone on a 640? I'm not as concerned about taking flight in the mud, because mud buildup takes a little time and gives you plenty of visual warning.

See anything I'm missing?

[turkish]

Originally Posted by sherpa

The only thing that gives me concern about keeping the low guard...is the issue of The Perfect Rock... getting caught in there and causing the front wheel to quickly lockup unexpectedly...resulting in me taking a little flight over the bars. Has this actually happened to anyone on a 640?

It never happened to me in 30,000 miles with the same front-end on my 950. Rocks would get up in there, but they'd be spit out. Besides, that fender isn't all that strong and anything big enough to jam up and spit you over the bars would probably rip the fender apart first.

[sherpa]

Originally Posted by turkish

It never happened to me in 30,000 miles with the same front-end on my 950. Rocks would get up in there, but they'd be spit out. Besides, that fender isn't all that strong and anything big enough to jam up and spit you over the bars would probably rip the fender apart first.

Yeah...that's my thinking too...but I thought in my travels over in OrangeCrush...I came upon a report of someone taking flight from The Perfect Rock...with the law of averages, one or two incidents don't bother me...but I'm a noob to the KTM thing and was wondering if that one report I read was the tip of a larger iceburg...

[Renazco]

Originally Posted by sherpa

Sounds great...I can PayPal you some money anytime your ready...just let me know.




Here's my thinking about the low/high guard issues at present...subject to change at anytime though.

The low guard works better at keeping shit off me and the bike.
The low guard MAY allow more airflow and thus better cooling.
The low guard can become clogged with sticky mud causing front wheel lockup.
When you do get the front clogged with mud, the cross over brake line makes removing the guard a PITA.
The low guard can bottom out on the lower triple clamp under full compression...although the guard is a very flimsy thing which wont harm anything by hitting the lower triple.

So...I might try the mods below for awhile prior to converting to the high guard.

Raise the low guard by 5/8" giving me a total of 1 1/2" of clearance to the tire. That's with the supplied Sahara 3's... will probably be less with knobbies.
Replace the cross over brake line with a second line direct from the master cylinder.
Modify the black,plastic, brake line guide that now sits below the lower triple clamp. I'll need a second one of these on the right side for the second brake line. This thing is held on by four bolts...overkill...I'll cut away the center section leaving me with one per side with each held on by 2 bolts...this will give me another 1/4" of clearance before things go BANG.

The only thing that gives me concern about keeping the low guard...is the issue of The Perfect Rock... getting caught in there and causing the front wheel to quickly lockup unexpectedly...resulting in me taking a little flight over the bars. Has this actually happened to anyone on a 640? I'm not as concerned about taking flight in the mud, because mud buildup takes a little time and gives you plenty of visual warning.

See anything I'm missing?

Low fender also adds to better stability, doesn't generate the turbulance of a high fender. Low fenders can get mucked up bad with mud which is why a fender for every season makes sense.
I'll send you the fender tomorrow, show us some pics when your done..

[warewolf]

Originally Posted by meat popsicle

Is there some way to restrict fork travel internally?

Yes, I believe so. Others have mentioned "travel limiters" when lowering the bike.

You could raise the oil level to resist bottoming, but this would also make the mid- to late-stroke harsh.

[warewolf]

Originally Posted by Ant Ware

I noticed the new 990's have a slightly raised front fender

Hmmm maybe the fender and the second brake line can be retrofitted? Might be an easy solution - but again, there'd be a clearance issue.

[Surly]

Originally Posted by sherpa

Yeah...that's my thinking too...but I thought in my travels over in OrangeCrush...I came upon a report of someone taking flight from The Perfect Rock...with the law of averages, one or two incidents don't bother me...but I'm a noob to the KTM thing and was wondering if that one report I read was the tip of a larger iceburg...

Perhaps and excuse for an incident where someone grabed a handfull of front brake in a rocky situation?
(I say that based on eye witness accounts of other misfourtunes)
I was'nt there but I'd think that the fender would explode or the tire would slide before someone would get tossed.
Like I said tho I was'nt there

[meat popsicle]

Originally Posted by warewolf

Yes, I believe so. Others have mentioned "travel limiters" when lowering the bike.

You could raise the oil level to resist bottoming, but this would also make the mid- to late-stroke harsh.

"travel limiters" eh? - thanks for the reply warewolf!

did a search and some call them "spacers"; one hit talked about doing it when dropping the rear, so if you go this route sherpa, you might have to lower the rear to balance the change... unless you have already considered this and dismissed the option.

[warewolf]

Originally Posted by meat popsicle

did a search and some call them "spacers"

Be careful of the terminology there...

Spacers is a term frequently used when adding preload to fork springs. They will not limit travel - although it will increase the force of the hit required to cause bottoming - not the same thing.

[meat popsicle]

Originally Posted by warewolf

Be careful of the terminology there...

Spacers is a term frequently used when adding preload to fork springs. They will not limit travel - although it will increase the force of the hit required to cause bottoming - not the same thing.

Ah! Thanks for the clarification. That site must have been unclear; or my reading comprehension was on the fritz again...

[warewolf]

When I say, "there" I mean, "in general". The site to which you refer may be correct. I'm just flagging it as a potential source of confusion.

[BSTARD]

I used to like my low fender, I still like it as I still have half of it on me bike

The part that causes the front wheel to lock up is the brake line cross-over. I would think that given enough mud without the cross-over the fender itself would maybe lock the front wheel, maybe. If you raise the fender and keep with the cross-over type brake line you will more than likely find that the original isn't long enough for the job anyway and a new one will need to be custom made. You could remove the cross-over brake line and add a new brake line routed to your brake lever, this would eliminate the cross-over lock up and you keep your low fender. You could replace the cross-over brake line with parts for fitment for about $150AUD.

I would just use some 3mm aluminium sheet to fabricate the "spacers" to raise the fender. As far as the reduction in suspension travel caused by raising the fender, If you plan on using all of the bikes suspension travel I suggest you obtain a new front rim cause your gunna need it

High fender issues;
Reduction in cooling - haven't noticed any difference.
Stability - haven't noticed any difference.
Cleanliness - dirt is good.

Interested to c how this turns out, and keep us posted with lot's of pic's

Cheers.