1200 bandit newbie chasing some more power!

[HarryH]

Hello chaps and chapettes,

Recently started a rebuild on my 97' b12.

I've got the engine on the bench and whilst everythings being painted and getting new bearings etc I thought i'd look into boosting the power out of the old thing.  I'm completely green when it comes to much more than air filters, jets and exhaust systems.  I've treated the bike to a full new system, a new K&N and some bigger main jets so far to accommodate the full system.

 

Can someone please go into the modifications like head skimming (I have absolutely no idea of how much can be removed without damaging anything or running into problems)

 and GSXR cam installations with me as to whether its worth it?

the other option being a '750 dot head and gsxr cams' once again, I'm not particularly clued up on that aspect either.

Thanks

 

[Rabs]

If youre going to trouble of head skimming why not get the head gas flowed ?

think it was worth about 10 horse on a 1052 way back when

im sure someone will know better than me 

[wraith]

Welcome to OSS 

As someone will say, read the rules in the general section 

Tuning the b12, first how much money do you want to spend?

1.Big bore to 1216cc standard b12 head with gsxr cams (750k I believe are the best), will get a good hick in bhp for the bosh

2. Standard bores, DOT head with gsxr cams not as much increase in bhp, but much cheeper.

3. Gsxr750 38mm carbs on ever of the above.

End of the day as I ask above how much do you want to spend as you can keep going and going and do you want top end power or bottom/mid torque?

 

[johnr]

turbo? depends how much you want to spend, but in terms of pounds spent per bhp its probably the best result.

[Kurf]

Speed is just a matter of money... How fast can you afford to go? 

[colinworth79]

Hu As above what do want to achieve first,

standard motor with decent exhaust and filter 115-120

bit of head work and cams 130 ish

 

1216 /1246 big bore and flatsides 150 ish

low comp pistons , corrillo rod , port job turbo up to 300

day to day road bike I would have it how I had my bandit back in 2003 1246 big bore , full akro system , yoshi cams and gas flowed head 145-150 hp .

Budget to replace the old cheap (crap from new ) shock , rework the forks and some decent sticky tyres .

The old girl back in the day -

[HarryH]

Sorry been out at work,

Current situation is the bike has swallowed most of the budget being rebuilt (bearings, paint, powdercoat etc)

I could probably afford to throw about £400 at it right now however further down the line more money is not a problem.

Would £400 be adequate to achieve anything?

[clivegto]

Dot head & exhaust.

[MeanBean49]

With £400 i would look at getting an ignitech cdi, some gsxr 750 cams, pod filters, race can and some dyno time. Should be good for 125-130bhp

Personally i dont see the point in whole dot head swap. For 15bhp when you get 10bhp from the cams on there own without the extra work, cost and getting round the issues with different carb angle. Plus if you go big bore in the future the compression gets too high with the DOT head. Better off just having standard ported at a later date.

Edited February 1, 2018 by MeanBean49

[johnr]

400 quid? tyres and track days. if you cant make speed on the straights, learn how to maintain it in the corners.

[nlovien]

without knowing your reasons why and what i'm in the johnr camp - if your not into track days - still focus handling and tyres - stuff for free is drop the forks  5 to 10mm, for not a lot adjustable dogbones to let you play with rear ride height, a 3 tooth  larger rear sprocket to give you some free performance and if yir tyres are good then look for a half decent rear shock

[johnr]

are you saying im camp?

 

[HarryH]

Sorry. Should have clarified. 

I already know how to ride the bike, been riding since I was a nipper. Bike has progressive springs and a cbr600RR4 rear shock so doesn't handle badly either. 

[bluedog59]

No point in making 140bhp with a 100bhp chassis and brakes.

A good full system exhaust and jet kit is enough for a B12 to start getting out of shape with "enthusiastic"  use.

[Dezza]

Removing the head and barrels and then replacing them correctly will eat up a sizable chunk of £400 due to the costs of the multitude of gaskets and seals required. This  will not leave much for any specialist labour costs and parts for any increase in bhp needed to wobble more quickly to the next corner on stock suspension. I think.

[dupersunc]

Have you considered wearing your under pants on the outside of your leathers?   

Edited February 1, 2018 by dupersunc

[bluedog59]

Actually, with £400 I'd fit some lighter wheels from a more modern bike.  It will accelerate faster, stop better, be easier and more agile through bends and give the suspension an easier time. Loads of worthwhile improvements with zero reliability issues

[Madb]

+1 on the above what  bluedog59 said. handling and brakes before performce. £400 quid should get ya fair way up the ladder.

[MeanBean49]

Couldnt agree less on the handling thing where its a road bike.

A bandit 12 handling is goid enough to scrape the pegs and bend the brake and gear levers on track. Which is more handling than your ever likely to need on the road. You can always use more power and a bandit chassis is more than capable of handling over double the stock power without issue.

 

[HarryH]

This is the problem I'm having, the bike has already been resprung and has a new rear shock, braided hoses throughout. It handles fine! I just want more poke lol.

Glad to know I'm on the same sheet as you. 

[nlovien]

once you've got decent handling to your liking ( sounds like you do ) - on my list next would be a decent set of carbs - a set of smoothbores in replacement of CV,s  - £400 marginal but should be enough to go fishing for 2nd hand set - good thing is you gain on immediate fitment plus they add to any future development - and they are cost recoverable when you come to sell on

[Oilyspanner]

You'll get lots of ideas  Harry from us board/bored members for your 'bandit project' ! - all have merits. 

The first big bang for pound will be : race can, higher flowing air filter (or dual pod filters) and a jet kit to suit - a trip to a good dyno operator for carb set-up will get the best from this and be quicker than fiddling with jetting options. An ignition advancer helps with pick up a bit and the lower the gearing is a good shout (the cheapest way to gain extra thrust, drop a tooth from the front sprocket is easiest/cheapest).

Stage 2 will be a bunch of the ideas above - cams,big bore, head flowing and full system being good value for big grins - the carburation will need to be adjusted after this. The 36mm cv carbs can still flow enough air for 150hp at best, but do help to make a smooth and torquey power delivery - better flowing carbs will make bigger numbers more likely, but won't match the first half of power delivery of the 36's.

It depends what you want/expect ..... the options are as big as your wallet !

[HarryH]

On my mobile whilst at work. Really appreciate all the top advice I'll reply properly later

 

Thanks guys

[HarryH]

12 hours ago, dupersunc said:

Have you considered wearing your under pants on the outside of your leathers?   

Actually laughing out loud.

 

Although I wear jeans and textile jackets so I couldn't possibly fit this criteria