Replacement Rear Springs

frogdon · Post by **frogdon** » Mon Apr 09, 2012 12:53 pm

I've been scouring the net for ages, and I just can't find any information on the stock springs for the CB400 (Project Big one). Any one know these?

Essentially, I'm looking to tart mine up (it's raining, and I can't go and polish any more or spray my side panels

), so I'm sourcing new shiny bits to apply

I don't really want to lose the stock shocks as a) they look cool and b) I presume they're better than Hagons if they're in reasonable condition. I've finally found some springs, but although I've found the length (225.3 mm according to the manual), I can't find any indication of the rate.

Anybody any ideas?

Also, if anyone's ever dissasembled the shocks and has any do's or dont's, that would also be much appreciated.

I REALLY want to get this on the road before the end of summer....

amorti · Post by **amorti** » Mon Apr 09, 2012 11:59 pm

Remove them, and send for powder coating? They can do chrome coating now if you fancy shiny, and it's just the excuse to remove any other brackets that could do with freshing up and send a batch away.

nictecninja · Post by **nictecninja** » Thu Apr 12, 2012 12:58 am

Hey dude,

I've got the same ride & have been goin throu some simlar probs. I have to agree that the standard shocks look best & yes you can strip the springs off very easly & powdercoat them but I am still trying to find out about rebuilding the damper unit.
Just to let you know I have purchased a very nice set of piggy back showa's of a 92 CB 750 they look identical but obviosly have a harder spring rate (not a prob @ 15 stone on softist setings) & are a little longer @ 355mm eye to eye compared to 325 eye to eye, I like the raised rear end thou, pic's of my ride to follow soon work pomiting.
Anyway hope this help's & post some pic's of your ride / work in progress.
Later dude.

frogdon · Post by **frogdon** » Sat Apr 28, 2012 1:50 pm

Sorry chaps, completely missed the e-mail I got following your replies.

Amorti, I was trying not to take it off the road, although that might no longer be an issue, as it would seem I have something very wrong with my engine. I was getting no power above 3k revs, which I thought was as it was running rich and fouling the plugs. I've replaced the plugs, and I get exactly the same behaviour, although I now know that it's throttle related - give it a little gas, and it'll get to 3k and bog down (bike starts to slow as if brakes have been applied) take a degree of throttle off, and it starts accelerating again. Looks like I might have time for a powdercoat after all.

My pub landlord also runs a spraypaint shop, so I might be forced to go to the pub to see if he can powdercoat as well.

Nictec, I've found loads of springs on the magical ebay, for various 450's which I think I'll investigate... cheers for the tip. I'll pop up a thread in the show and tell when I get back from work. It's not much yet, but given my mechanical skills, I'm happy!

Superjack44 · Post by **Superjack44** » Sat Apr 28, 2012 4:33 pm

Check your airfilter make sure there are no mice in there

frogdon · Post by **frogdon** » Sat Apr 28, 2012 5:00 pm

I'm not sure how you keep your bikes, but....

I'll check that tonight.

frogdon · Post by **frogdon** » Thu May 03, 2012 6:58 am

Alas, no mice. Air filter looked fine, felt around all the carb ports and couldn't feel any blockages (in fairness couldn't feel very far in!). Also could only feel a shutter on one carb (couldn't really reach two of them, but couldn't find one on cylinder 2).

Anyways, decided to take it out for a low rev ride to see if cleaning it would help. And it has

Still a massive flat spot, but this seems to have moved up to 7k RPM. When it gets through this, it goes mental!

I'm still looking to sort my springs but, for the moment, I'd forgotten how good this was to ride, and I think I'll just spend a bit of time with it on the road

That'll give me time to find some new springs or shocks. I'll be watching....

nictecninja · Post by **nictecninja** » Thu May 10, 2012 1:08 am

Hi ya dude,
quick tip, make sure that the small breather in the tank is clear by blowing throu pref with a air line.
I found mine was blocked & was causing running probs, hope this helps laters

Superjack44 · Post by **Superjack44** » Thu May 10, 2012 11:32 am

nictecninja wrote:Hi ya dude,
quick tip, make sure that the small breather in the tank is clear by blowing throu pref with a air line.
I found mine was blocked & was causing running probs, hope this helps laters

This happened with me too but I was unable to blow it clear (bike had stood 12 years) so I used a length of broken throttle cable to push through from underneath the tank into the smaller of the two pipes I twisted and pushed at the same time and eventually managed to clear it.

frogdon · Post by **frogdon** » Thu May 10, 2012 12:57 pm

Cheers both. I have checked it in the past, but I'll check it again.

It's working much better at the moment, just a gentle knocking (rear wheel bearings or tight chain link, although I can't see anything immediately wrong).

Seems to increase with road speed rather than engine speed, so I'll get the bearings checked over tonight.

Thanks for all the help

Replacement Rear Springs

Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs

Re: Replacement Rear Springs