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Discussion Starter · #1 ·
Hi guys,
So over the last week I've noticed the bike feeling very weird under heavy braking and cornering (like the rear wheel is lifting/bouncing). Also that there was very little resistance and a lot of travel in front forks. I asked one of the lads from work to take a look (he is an ex motorcycle riding instructor) and he said they are not leaking but there was very little shock absorption and that it needed a fluid change. He also said the springs were fine. I normally would take on a repair like this myself but I've noticed there does not appear to be a drain bung and fluid change may require forks to be completely removed and inverted. (Does this sound right?). Could the problem be something else?


My bike now has 11300km's on the clock and is outside its warranty period. I bought the bike new March this year. I weigh 90kg and the bike is my daily commute. (just trying to provide as much info as possible)
 

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With only 11K on the clock there shouldn't have been any change in your forks. Its usually when the fork seals get worn and you lose a bit of oil that they get a bit spongy.
As they are non adjustable, I cant think what could have changed. Have you tried upping the preload on the rear spring a notch? Nothing to lose.
If you wanted to chuck some money at your bike then you could fit stiffer fork springs and/or emulators. A cheaper option is to add more fork oil or change to a different wt oil.
 

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Discussion Starter · #3 ·
Is there a way to add/remove/replace the fork oil without removing the forks from the bike? At the moment ill up the preload one notch but im really not hopeful on that.
 

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If you want to replace the fork oil then its probably best to remove the fork legs so you can use gravity to assist you and get a good drain.
I've just had the fork legs off my GSXR doing the fork seals, its not a bigger job as it sounds but you need to get the weight off the front end to do it. I really cant see how how your fork oil should need changing at 11K. I've got 13K on my bike with lots of hard riding on bumpy back roads and its just the same as when I bought it, which isn't fantastic but its a bike built to a price point.
I haven't had the caps off the top of the CBR forks but usually you can do this with them on the bike once you have taken the weight off the forks. Do you have a good rafter in your garage/workshop you can hoist off?
Then its just a matter of pouring in another 10 or 20ml of oil at a time and test riding in between top ups. Alternatively you can remove oil with a suction pump that has a small diameter tube. Doesn't sound like you need to remove any tho!
Forum member @DaBinChe is a bit of a suspension upgrade guru, check out his vid clips on pulling the forks apart.
 

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If you want to replace the fork oil then its probably best to remove the fork legs so you can use gravity to assist you and get a good drain.
I've just had the fork legs off my GSXR doing the fork seals, its not a bigger job as it sounds but you need to get the weight off the front end to do it. I really cant see how how your fork oil should need changing at 11K. I've got 13K on my bike with lots of hard riding on bumpy back roads and its just the same as when I bought it, which isn't fantastic but its a bike built to a price point.
I haven't had the caps off the top of the CBR forks but usually you can do this with them on the bike once you have taken the weight off the forks. Do you have a good rafter in your garage/workshop you can hoist off?
Then its just a matter of pouring in another 10 or 20ml of oil at a time and test riding in between top ups. Alternatively you can remove oil with a suction pump that has a small diameter tube. Doesn't sound like you need to remove any tho!
Forum member @DaBinChe is a bit of a suspension upgrade guru, check out his vid clips on pulling the forks apart.
I see you took the fork nuts/caps off. Obviously having to take the load off the front end and extend the forks fully. Were the caps hard to get off? Think they are 14mm? I was toying with the idea of putting preload adjusters on them, they come with 2 short tubes that say they go inside the top fork as well? Did you have anything fly out when you did it? Just want to make sure no spring or seal pops out when I do it. lol
I just installed a Fork Balance Brace. I go over quite a lot of bumps and my driveway is a huge bump and steep incline after that. I have to stand up on the pegs to get up it. I figured it might help with any flex there may be. Honestly, I can feel the difference, especially on real curvy turns. The front wheel feels like it's being pushed down now and grabs great.
 

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I see you took the fork nuts/caps off. Obviously having to take the load off the front end and extend the forks fully. Were the caps hard to get off? Think they are 14mm? I was toying with the idea of putting preload adjusters on them, they come with 2 short tubes that say they go inside the top fork as well? Did you have anything fly out when you did it? Just want to make sure no spring or seal pops out when I do it. lol
I just installed a Fork Balance Brace. I go over quite a lot of bumps and my driveway is a huge bump and steep incline after that. I have to stand up on the pegs to get up it. I figured it might help with any flex there may be. Honestly, I can feel the difference, especially on real curvy turns. The front wheel feels like it's being pushed down now and grabs great.
There's not that much pressure on the caps once the weight is off the forks.
Have a look at DaBinChe's clip below. You don't have to take the forks off the bike tho.

https://www.youtube.com/watch?v=WPyStuP9cj4

Interesting about the fork brace, not something i had thought off. Those spindly 37mm forks need all the help they can get. I see the R3 has 41mm forks. Better for rigidity.
 

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so looked over and don't trust them to do anything, just there for looks....my mountain bike fork arch is beefier then the ebay braces. The plate thinness cut out and how it is attached to each side tells me it is for looks. I contacted SuperBrace and asked them to make one for the 250/300r/f.....maybe if more folks contacted them to ask for the same thing they will come around and make one.
 

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Fyi...

so looked over and don't trust them to do anything, just there for looks....my mountain bike fork arch is beefier then the ebay braces. The plate thinness cut out and how it is attached to each side tells me it is for looks. I contacted SuperBrace and asked them to make one for the 250/300r/f.....maybe if more folks contacted them to ask for the same thing they will come around and make one.
Interesting read...for those who are debating...

Fork Brace Group Buy? - Honda CBR250R Forum : Honda CBR 250 Forums
 

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Ari Henning fork video...

If you want to replace the fork oil then its probably best to remove the fork legs so you can use gravity to assist you and get a good drain.
I've just had the fork legs off my GSXR doing the fork seals, its not a bigger job as it sounds but you need to get the weight off the front end to do it. I really cant see how how your fork oil should need changing at 11K. I've got 13K on my bike with lots of hard riding on bumpy back roads and its just the same as when I bought it, which isn't fantastic but its a bike built to a price point.
I haven't had the caps off the top of the CBR forks but usually you can do this with them on the bike once you have taken the weight off the forks. Do you have a good rafter in your garage/workshop you can hoist off?
Then its just a matter of pouring in another 10 or 20ml of oil at a time and test riding in between top ups. Alternatively you can remove oil with a suction pump that has a small diameter tube. Doesn't sound like you need to remove any tho!
Forum member @DaBinChe is a bit of a suspension upgrade guru, check out his vid clips on pulling the forks apart.
(CBR 250 R..same forks as the CBR 300 R )
https://www.youtube.com/watch?v=k884DfM2LsU
 

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Just looked at the thread and they went with the bikerbitz. It is beefier then the ebay brace but I still don't like the way the plate attaches to the fork clamps. It is a 5pc design and the plate just sits on and bolts down. Also seems like the fit is a little off cause they had to enlarge/elongate the mounting hole.

I rather have the SuperBrace it is a two piece design so would be more ridged. The arch and clamp are solid with each other. I rather pay more for a better quality product made in the USA.
 

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I'm keen on the idea but like DaBinChe, i would only fit a quality product.
I see in this photo of Ari's 300R there is no brace either.

Ari Henning.jpg
 

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If Ari thinks that it is not needed......and he is quite knowledgeable...who am I to argue.:) So I will not endure that cost.


Has anybody read or seen videos of his thoughts on the 300 R in race trim?
 

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Has anybody read or seen videos of his thoughts on the 300 R in race trim?
No but I haven't really searched properly. It would be interesting tho. I did contact him once through his facebook page and he replied in timely fashion which was appreciated.
 

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Is there any debate about whether fork braces work, or not? I can't say I know much about them. If they DO work, and obviously they add very little weight, surely a racer would use one if the rules allowed, unless there is a downside? Maybe the reduction in sideways flex is a bad thing when cranked over, in that it reduces the ability of the forks to absorb bumps?
 
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