forks bottom out nc24

[triton]

just starting to ride my nc24 just bought noticed it bottoms out on hitting speed bumps or if push ing down hard is this normal or could it be short of fork oil.is it easy to change oil only got nc 30 manual.

[Old Painless]

What do you weigh ?

[Neosophist]

Lots of old Hondas have 'soft' forks.

When you say bottoming out, do you mean they compress a lot (normal)

Or your getting a physical 'banging' where the forks are running out of travel?

The forks have an anti-dive system that if working properly should prevent them bottomging out over sharp bumps as it alters the flow of oil.

There quite different to ride from newer bikes where the suspension is like 'iron'

First things i'd check if you are getting a banging are.

1. Anti-dive system on Left fork
2. Fork Oil / Air quantity


Fork oil is similar for most forks... Undo the drain screw at the bottom and allow the oil to drain.

[triton]

Lots of old Hondas have 'soft' forks.

When you say bottoming out, do you mean they compress a lot (normal)

Or your getting a physical 'banging' where the forks are running out of travel?

The forks have an anti-dive system that if working properly should prevent them bottomging out over sharp bumps as it alters the flow of oil.

There quite different to ride from newer bikes where the suspension is like 'iron'

First things i'd check if you are getting a banging are.

1. Anti-dive system on Left fork
2. Fork Oil / Air quantity


Fork oil is similar for most forks... Undo the drain screw at the bottom and allow the oil to drain.

yes it bangs will check see if theres any oil in it.cheers

[duncan]

They all do that sir.You have to remember that this bike was originally designed for a Japanese rider and they tend to weigh a lot less than British ones and also that it is over 20 years old and things do wear out.The only real answer is a better quality set of fork springs.I have used Maxton ones.They are aroud £70 and you will have to send off your old springs and spacer and tell them how much you weigh.Maxton have a website which you could google.I would not pump air into the schrader valves on the fork tops because there is then a big risk of blowing the fork seals

[Neosophist]

They all do that sir.You have to remember that this bike was originally designed for a Japanese rider and they tend to weigh a lot less than British ones and also that it is over 20 years old and things do wear out.The only real answer is a better quality set of fork springs.I have used Maxton ones.They are aroud £70 and you will have to send off your old springs and spacer and tell them how much you weigh.Maxton have a website which you could google.I would not pump air into the schrader valves on the fork tops because there is then a big risk of blowing the fork seals

If you are using cheap forkseals.

Air is fine if you have proper Honda seals... 11psi I run in mine. 10w fork oil.

Had to replace a bush in the anti-dive that had ovaled but apart from that it all works as intended.

I dont' weigh much though.. :)

[Lope]

I second Neo on the air. I put 0.75 bar in mine (11psi) and its a MASSIVE improvement. I hated my front shocks before that. I weigh 75KG.
Be sure to only use a bicycle pump, and just give one pump before you take a reading. Those things hardly take any air, and you can blow the seals easily. You probably shouldn't go over 11psi.

[triton]

thanks guys im a slim 13 1/2 stone 62 year old,i will change fork oil and maybe but a bit of air in them.will let you know how i get on.not all japs are small have you seen those sumos they make me look slim

[graemenc24]

I had the same problem as you triton. It is nothing to do with how much you weigh mate. Trust me something is badly wrong. I had the same clonking sound when i went over a bump in the road and just pushing down on the handle bars and squeezing the front break i got the same noise. It turned out that the so called mechanic who sais he done both my fork seals when i first got the bike was a c@*t. With little knowledge of bike mechanics i rang a friend (ian daly) and he confirmed by listening down the phone that the noise was a bad one. He thought it was the anti dive system. I decided to have a go myself at sorting the forks out. The first attempt involved me sucking out 300 cc's of the fork oil from each leg and adding 300 of 15w back in on both forks. The result was no change still clonking. What i did find out though was the fork oil in the left fork was new and clear and the other fork oil was jet black and stunk. Hmmmm i thought that grease monkey was meant to have changed the oil in both and done both seals! I rang the twat up and said excuse me can you tell me what weight oil you put in both my forks please. He said mmmm 5 weight thats what's reccomended. I knew then he was lying as we all know the rec is 10w or higher. I called him all the names under the sun and then it clicked... hang on if he never done the job he said he did then maybe i should start from scratch. So ten days ago i drained out the forks and noticed there was only 300 cc in each leg! Well short of the right amount. I compressed the forks completly and filled each fork up with new 15w to within 90mm of the top with the springs and spacers removed. (i used a knitting needle and marked 90mm with a bit of tape to get exact measurement. So when needle had fork oil on and the tape was level with the top of fork tube it was exactly right). Put the springs and spacers back put caps on after jacking up bike and hey presto....perfect suspension again. Did not even need to put any air in them either but i did but only 8 psi (the bottom level recommended) Now i ride about and dont worry about speed humps or pot holes its great. PS the spacers in the right fork are 10mm longer than the left so make sure you put them back in the correct fork leg. Hope this helps unless you have sorted it already. Now i have a new problem with bike that needs sorting i think the starter relay is kaput!

[Neosophist]

Fork oil is 389 / 392 cc of 10w oil (right leg / left leg respectivly)

Fork oil level is 90mm (measured from TOP of tube) with leg fully compressed and fork springs removed...