Hi all,
so my cb400sf failed the mot:
there is too much side to side freeplay in the swingarm....

the tester told it was so much that it seemed like there was some spacer missing...
he also gave me a hint, just put a spacer and it will pass....

Any of you had similar issues?
the annoying thing is that i have to remove shocks, wheel and the the swingarm to check the situation....

If there's that much play, then when you fix it you'll find the handling a revelation. Stop whinging and get it done.

I can't imagine a spacer is missing, as that would mean it'd have to have been forgotten when the bike was last apart, which it doesn't sound like you will have done recently. More likely is a dried out and collapsed needle bearing. Either way once you get it apart you'll soon know the issue.

From left to right the shaft should have:
needle bearing with bush/spacer/roller thingy (could have broken up)
centre spacer
two cartridge ball bearings (could have play)
spacer part.

The ball bearings are cheap and easy enough to fit. The needle bearing less so, but don't skimp.

It will make it easier to remove and refit if you slacken off the engine mounting bolts.

hi,
I bought the bike couple of months ago and never dissamble anything near there...

it's not a hard job, it just annoying me the fact that i have to remove shocks and wheel to get the swingarm out...

I was thinking (only as a quick temporary fix) to just remove the pivot and try to stick a washer (24mm if i got it right)between swingarm and frame, just to pass the test and then with calm dissamble everything....

why bodge something that could effectively fail and potentially cause a dangerous situation. Your bike has failed its MOT for a reason. As stated above, dont skimp, do the job properly and the bike will be safe and pass its MOT.

Vparts wrote:why bodge something that could effectively fail and potentially cause a dangerous situation. Your bike has failed its MOT for a reason. As stated above, dont skimp, do the job properly and the bike will be safe and pass its MOT.

Seriously, stop whinging and get it done right. With play in the middle the whole bike will handle and steer dangerously.

It doesn't get any easier than doing this on a small bike with a mainstand. You're complaining about removing the wheel (one nut to remove the axle) and the shocks (one nut/bolt each). MTFU. On what bike can you possibly imagine this would be easier? On a bike with a monoshock with linkages or without, it'd be worse for access so a harder job.

My Fireblade wants steering bearings and fork seals. On a CB I'd put it on the stand and strap/weigh down the rear for an easy steady platform, as it is I'll probably have to take it to the shop.

you are all right guys, i was considering that because the tester gave me the hint, " it only needs a washer or probably a spacer and it will be fine"...

I have some tools at home but i don't have one big enough for the wheel nut, plus yesterday i looked at the swingarm nut and it looks like is deep in the frame so i would need one of the T style wrench...
I do have a friend who is a car mechanic and will help me with the job but he would need to borrow those tools from work...
Actually, do you know by any chance what spanner size do i need for the wheel and the swingarm nut???

Anyway i will get it done properly...

This morning i had a close look and basically the play is about 5mm!!!!

5mm play is a massive amount, I am surprised you can still ride it confidently at all.

Off the top of my head the rear nut is 24mm on these, 27mm on the CBR400. I think the swingarm nut is actually the same size, since the spindles are both 17mm diameter.

Go round to your car mech mate, he will have an impact gun and the right deep sockets, and whizz both off in moments. It's the best way to get off nuts which might be seized, much less risk of rounding them, which you will do with a spanner even if you could get it in on the swingarm nut.

As said, slacken off the engine nuts to ease removal and installation, though with that much freeplay it'll probably fall out the frame in a pile of metal shards.

Either - buy all the bearings in advance and expect even for an amateur to be in and out in 3 hours. Or - take it apart thinking maybe you don't need to buy the bearings, end up putting it back together still broken, and doing the whole lot again next weekend. Basically, you'll want all three bearings. Buy them, swallow the cost, and get the job done in one sitting. You mechanic mate will have a pot of suitable grease for the needle bearing, and a bearing puller and/or suitable drift.

You'll owe your mate some beers for this too.