I have a slight problem, today I replaced the brake lines on my Thundercat on the front brakes due to them being really spongey, however things have gone slightly wrong and I’ve ended up with no front brakes now
I’ve tried bleeding the brakes and fluid comes out of the bleed nipple and leaves the reservoir, it’s slow really slow coming out but still comes out none the less. Now I though all the air was removed, so tried the brakes and nothing at all, I might as well have not been applying them
So I thought it was a bit strange, so bled again, once again fluid comes out and still no go, so I checked all the banjos and as I undone them fluid came out, so figured they was all fine, so I bled again after that but still no go
I currently have the lever cable tied back and can push the bike about with ease, I’m hoping this will do something and I will check every so often and top fluid up if need be
I doubt this will do anything, does anybody have any tips at all? Failing that, is somebody able to come out to me in Stoke Poges, just outside Slough and sort them out for me, I’m very much willing to pay, at the moment I can’t drive anywhere as I have no front brake so would need somebody to come to me
Not that I’d recommend it but I rode my bike 25 miles to the workshop on just rear brakes once when similar happened to me…you’ve got to plan a bit in advance though!
Your problem is just that you have air in the system still - keep bleeding them. Just in case, the method:
pull brake lever
open bleed nipple
close bleed nipple
let go of lever
If you are seeing very little fluid come out, keep going. If you’re seeing lots of fluid come out with any bubbles at all, keep going. A general rule I use is if I can do 5 pumps with only fluid coming out and no air at all, check the brakes and if they’re still soft move somewhere else for a while. You may also need to do similar but crack the banjo at the master cylinder as a final measure.
I think I remember thundercat brakes are dual bleed each side? If so, that might take a while…
I’d add to the Alex’s method by pumping the brake lever 3-4 times, it should start to feel firm then hold it on, this needs to be done with an assistant as you need the brake held on while you do the necessary with the bleed nipple, note as you release air/fluid through the bleed nipple the brake lever needs to be pulled into the handle bar.
Open bleed nipple
Close bleed nipple
Pump brake lever to repeat
Bleed one side (the side nearest the reservoir) until you get clear clean fluid coming out, then bleed the other side, repeat both sides just to be sure to be sure.
Bleeding the brakes doesn’t seem to be working for me
I just called a guy up from Gumtree who does mobile mechanics and he said he would come out to me for £50, is that a good price to do them? Can anybody beat that as well, would rather somebody on here do it…
Long way to ride from stoke poges though…I’d say go with the guy if you can’t get it yourself (I’d agree two people is better but I did both sides on my own with a bit of a stretch to get to the lever from the left)
Ok so the syringe didn’t really work, I’ve read a few forums saying that the brakes are difficult to bleed on the thundercats and some people say that you have to remove the calipers others say you dont’ have to.
I have also found out what crack the banjos mean, so will give that a try Alex, the problem is that guy can’t come out till Tuesday / Wednesday, although if it does snow I doubt I will be going anywhere anyway
Nah that’s fine Conrad, doesn’t sound like that at all, I thought it would be just a case of bleeding the brakes, something I have done before and with ease on my old NTV, but this time it hasn’t worked, guess I had beginners luck the first time I ever bled brakes lol
I’ll drop him a pm and see if he can and thanks for the offer mate
The snow has started settling here now, so doubt I will be using it at any time soon now
How were the brakes working before you changed the lines? If they worked fine then the system is probably fine. Try the syringe method again. Test all nuts are tight then attach the syringe tube to the bleed nipple. Fill the master cylinder reservoir. Now pull the fluid through with the syringe (top to bottom), the pressure will be tight but persevere until you see fluid appear in the syringe. The lever should be firm to the touch. Bleed as normal afterwards.
Rob, they was really spongey, had to pull the caliper in all the way before getting any pressure at all from them, I’m going to crack the banjos tomorrow and see how that goes, as I’ve read about that on a few Thundercat threads on other forums and will then use the syringe to pull through again and keep my fingers crossed
Pinch the tube where it meets the bleed nipple just to make sure there’s no air getting in when you pull on the syringe. Pull the syringe back BEFORE you tighten the nipple. If this works and you’ve got a firm lever then get a cable tie and pull the lever back and secure with the tie for 24 hours. It will help that loosening cover on the master cylinder reservoir and placing a towel on top will help.
Well thanks to Alex Golds tip of cracking the banjo, I now have front brakes I owe you a drink! Thanks for all the help guys, I would have done the rear brake caliper but one of the rear bleed nipples is stuck shot and I don’t have any WD40 and I’m snowed in so can’t go and get any so that will have to wait for another day