Q: I’d like to run a question by you guys regarding my new (used) Suzuki GSX-R 750 K7? I’ve always wanted one of these vastly underrated bikes and now I’m the proud owner of a blue/white one with only 16,000km on the clock and it’s very clean and completely standard, which means its never been messed with.

But I think the exhaust note is a little too quiet for my liking. So what I’d like to know is what horsepower did you get from a stock bike on your dyno and what could I expect if I fitted a full system or just a slip-on silencer regarding horsepower increase?

Looking forward to your response before I spend lots of cash?

Naidoo

A: A standard K6/K7 with a stock exhaust will make around 120hp at the rear wheel. But let me tell you that the stock exhaust is so hard to beat because the Suzuki headers are incredibly efficient. I’ve fitted well know brands (full systems) that have actually lost horsepower- how’s that!

So a full system (with mapping) might just make five horsepower and by just fitting a slip-on maybe only two, which you probably won’t even feel.

So my advice is to fit on a reputable silencer and enjoy the noise increase, and leave the headers alone for road use, and maybe even track use as well.

Q: Has anyone out there ever tried to fit, install and line up a new set of stainless steel spokes on a new and polished rim, well I have? 

W.T.F!

I have a Yamaha XT500 and I’ve recently decided to restore it and my first job is to rebuild the wheels, to be like new. And to be honest it’s sending me mental. Whenever I think I’ve got everything OK and spin the wheel – well, it isn’t OK.

I’ve watched many videos on the Net to help me, but I still can’t get it right. So can you generously provide any assistance in this very frustrating area, please?

Dave Gridley.

A: It is a bit of a ‘lost art’ rebuilding wheels to factory specifications, and to be honest we don’t even attempt to do it because, like you’ve said, it can become very frustrating to say the least.

Instead we leave it to the expert, who in this case is Alan Lawlor. He rebuilds all of our wheels, with spokes, on any rim you’d care to mention. So give him a call on (072 227 4125) and let him do it for you. Then you can sit back and concentrate on restoring the rest of the bike, what’ll probably send you mad as well.

Q: For the past ten years, or so, I’ve enjoyed riding my old Honda XL500R trail bike, I believe it’s from 1985, or so it says on the papers. It’s always been reliable and fun but it has always had an annoying oil leak from the cylinder head.

So I took off the head, because it’s not a hard job, and fitted a new and genuine Honda head gasket. Guess what, it still leaks from the same place?

So I bought another head gasket and did the same job, thinking it might have been a faulty gasket from the factory. Guess what, it still leaks!

So next time I was thinking of skimming the head and barrel to make sure both surfaces are totally flat and true. So my question, eventually, is how much can I take off these parts without causing premature detonation in the combustion chamber, because the compression ratio will obviously go up after the machine work?

I thought I’d ask before work commences, seeing as you work on engines and the like.

James Oxford.

A: I’m not too sure if this will cure your problem. This engine normally gives no problems. Are you sure someone hasn’t had something in-between the head and barrels and caused some damage to the surface areas before you had the bike?

But, if you decide to skim the parts you can easily take off 0.2mm from each surface with no adverse problems. This engine already has a relatively low compression ratio compared to today’s machines, so go ahead with your head skim and hopefully it’ll cure the oil leak issue? 

Don’t forget to replace the base gasket as well, while the barrel is off?

Q: Hello there guys and gals. I’ve just bought myself a 1976 Suzuki GT750 water-cooled old bus. It’s not in too bad a condition and I’ve managed to get it running nicely but the problem lies with the suspension, or to be more specific, the lack of it.

I cleaned out the forks and filled them with fresh oil and they seem to work fine for a model of this year but the twin rear shocks are f**ked to say the least.

I don’t really want to fit aftermarket rear shocks because they’ll look out of place. So my question is, can you or anyone else rebuild these shocks with new seals and oil so they perform like they did 40 years ago? If not what can I do or where should I look to get some new (ish) ones? Keep up the good work.

Kevin (water buffalo).

A: Unfortunately there’s nothing you can do to these old shocks besides throwing them away or hanging them up in your garage for a conversation piece. This is because they’re sealed units from the factory and cannot be taken apart.

So either look on the Net for original items (but they might be f**cked as well so be careful), or replace them with new ones from Hagon in the UK, for example. These work very well and still look relatively cool and retro.

Go to www.hagon-shocks.co.uk to see what they have for your bike.