GSXR750 SRAD needs some TLC

[Madmax1993]

I'm currently trying to put my 1999 GSXR back on the road, but the front brake calipers have seized (again). I was wondering if anyone knows what alternative brakes would fit as a straight swap or with an adaptor. I'm led to believe that a decent pair of 4 pots will be more reliable than the tokico 6 pots that are currently on there.

 

[Markybeau]

4 pot Nissins from Bandit 1200 of same era are the usual straight swap. Late 90's Tokico 6 pots are rubbish

 

[Madmax1993]

Thanks, I'll look into those, sounds ideal!

 

[Madmax1993]

https://www.ebay.co.uk/itm/19651675...nt12pUzRpS&var=&widget_ver=artemis&media=COPYFound a pair of calipers. Will they work with my existing lever? My understanding is that a 4 pot lever can't push enough volume of brake fluid to drive a 6 pot caliper, but the other way around should be fine right?

 

[Lucidone]

Can't answer your question directly but it's more to do with area than quantity. Six piston calipers often have smaller pistons. Hopefully @Markybeau might be able offer a definitive answer for that application.

 

[Markybeau]

Tokico's of this era were 'fussy' and needed regular attention. Yes they were standard fitment on ZX12R and Hayabusa, but see above. If you want just get on and go, the Nissins have better build quality, are lower maintenance and, for most riders, offer just as much stopping power. Unless you are riding at the limit of the bike, the Nissins are much less hassle.

The banjo bolts are different and the routing of the lines is different, so if you can get the calipers and appropriate lines you will save yourself a headache.

The ones you have pictured are the correct model. I don't know what your lever is, so I can't say. They should be compatible with your master cylinder though, unless it's non-standard.

 

[Madmax1993]

I put in a best offer of £130 and got them. Sounds like I'll need to order some hoses when the brakes arrive if the banjos are different as you say. Less hassle is definitely de rigueur in my case. I've had the tokicos rebuilt before, but the bike has sat outside for some time, so replacing the calipers with the nissins seems like a no brainer.
Thanks for the advice chaps, retrobike has never let me down, even on completely off-topic stuff!

 

[elite504]

Mmmm, SRAD, one of my most favourite bikes I ever had. Kept mine for 10-years and loved it.
FWIW, I appreciate you're on a trajectory, but the six-pots are very rebuildable.
Put the four-pots on and get riding, that's important. But for a nice fun therapeutic quiet-time job, the six-pots only require you to undo a couple of bolts to start stripping. The piston and seal bores corrode as they're not anodised or coated. The fluffy oxide pushes the seals onto the pistons and they jam up. If you're lucky, braking just gets bad. If you're unlucky, they drag a lot warping or distorting the disc too.

Rebuild kits are available from Wemoto, and as I say it's a fun job, just take your time and get everything spotlessly clean. Lots of cotton buds and dental pick action. Use red rubber grease on the seals. I think the Wemoto kit may actually come with it.

Once you've rebuilt, you can either pop them back on to go back-to-stock, or they're sought after on the aftermarket. Or at least they used to be. They bolt straight onto the 900/1200 Triumphs of the earlier 90's type (T300) and provide a useful improvement in braking for these heavy machines.

 

[Madmax1993]

Also, does anyone know what slightly 'ADV' style tyres come in the GSXR 120/70r17 and 190/50r17 flavour, or what wiggle room is there to fit a different width or profile on the GSXR rims?

 

[Markybeau]

Stick with a 180 on the back. You don't really need a 190 on a 750 of that era. More options, cheaper, and turn in quicker.