Horrible knock on SV

[Pete1987]

Hi all,

Bought my SV650SK4 a few months ago and new when i bought it that all SV's knock from the front end,

Is there a way to stop this as its gettina tad annoying now?

Thanks all


Pete

[orose]

It depends what you think the knock is coming from - they do make some strange noises, and it is normal.

Typical candidate is the front suspension which is under sprung for everyone except the most lightweight brit you can find, fixable for any depth of wallet (from a set of new springs in your weight right up to a GSXR front end conversion).

[G]

I have to say that mine doesnt knock....I would never buy something off someone who say 'oh they all do that, dont worry about it'

Sadly i cant offer any suggestions as to what it is though :(

[Pete1987]

It was someone on the org that said they all do it.

Would thicker fork oil slow things down a bit?

[Biker Biggles]

They benefit from a fork oil change every couple of years anyway,so it probably needs one by now.Worth checking that it is the normal fork clunk,as yours sounds particularly bad.Have you checked the head races,wheel bearings and brake caliper mountings?

[orose]

Graeme: can I move to where you live?
I guess your council takes care of the road a lot better than mine does. Theres a section on my way home from work which feels like its been lifted from a motocross track, and I haven't found a path through it which doesn't result in a clunk. I suspect the reason for it is to dissuade people from using the road, but thats another thread - this one has been hijacked enough.

[northwind]

Mine rattled like hell til I replaced the springs and oil, and then it stopped. No idea what caused it but I suspect it was the thicker oil that stopped it, can't see why it would be the springs. But then there's loads of causes for a front end rattle, some people blame the discs or the calipers, others the clocks or the headlights, some have found it was their head bearings...

If it's any consolation, I replaced the entire forks with GSXR ones and now I have a mudguard rattle which is worse than the SV one ever was, because I'm using the wrong mudguard :rolleyes:

[Pete1987]

I think it may be a case of the springs needing changing, where are the best place to buy some, i have read a little bit about maxton ones but cant find anything on their website.

Is there anything specific i should look out for?

Reason i think its the springs is because the forks in my NSR arent as squidgy as the SV ones and the CBR ones are also stiffer but that has more advanced suspension.

Thanks for all your help guys n gals.


Pete

[jambo]

Springs can be bought from Hyperpro, Hagon, Ohlins, Racetech, Maxton or a few others, they come in 2 types:
Linear have the same spring rate for the whole length of the spring
Progressive have an effective spring rate that changes with travel

Spring rates can be calculated for your weight roughly using racetech's site (http://www.racetech.com/evalving/english/Srchpr.asp?bikeid=396&manufacture=Suzuki&model=SV650S&year=03%2D07&TABLEINFO=street&langname=english)

Pretty please with sugar on top do a search, the topic on which is better is usually good for about 5 pages, and mostly boils down to "depends". If in doubt phone up Hagon or Maxton with your weight, riding style and budget and see what they recommend.

If you find the forks "Soft" this may be down to damping rather than springs, but if you weigh over about 12 stone the stock springs are likely to be a little soft for you anyway.

Before getting your wallet out get the front wheel off the ground and check the head races and wheel bearings etc are not loose ;)


HTH

Jambo

[larigos]

reading this thread as have a similar thing happening call me thick but how would you know/tell head races wheel bearing are loose by lifting the front wheel?

[embee]

To be honest I've always found the "rocking" test for head bearings is pretty vague, and the only really successful method is to actually adjust them. As soon as you start the adjustment you'll find out whether they are loose or not (they probably are, based on the 2 that I've seen).

Also you'll probably find the factory waved the grease tin somewhere in the vicinity of the bearings when they were assembled, so it would pay to drop the bottom yoke+stem down enough to get some grease in there, top one is easy.

[ljharmitt]

Can you hear the noise while the bike is stationary, or just when riding. If you can when stationary it could be the cam chain. Mine went and had to have engine rebuild so go and get it checked if its coming from the front.

[plowsie]

lj, read the thread mate ;) its about knocking front ends, you know, suspension, etc lol

[ljharmitt]

lj, read the thread mate ;) its about knocking front ends, you know, suspension, etc lol

Shush, dont make me look stupid :smt079 lol. Front end of bike i thought :rolleyes:

[Dangerous Dave]

Check the bearings first, then have a look for any lose cables which can cause a rattle every now and again.

Does it happen under braking or over bumps, if so then it is mostly likely the common SV problem which is easily cured with fresh fork oil. While you are at it you might as well get some springs to suit your weight too.