Increase in engine sizes
 

While out today Pegasus and myself were discussing cats being introduced on new bikes which increases the total weight of the bike and requires a bigger capacity to give the same output/near as performance as a non-cat engine. No doubt they are a lot more expensive to replace if damaged as compared to a standard exhaust.
This raised the question is it worthwhile buying new as against secondhand
The scenario I am trying to compare is the Triumph Sprint ST 955i against the new ST 1050 and in some parts of comparison the old 955i actually rates better than the new 1050.
OK the shape change I can understand but the 100cc increase seems to achieve little or nothing

WHATS OTHER PEOPLES VIEWS?

i.e SV--v's--Gladius

Re: Increase in engine sizes
 

Like any extra efficiency gained by modern car engines, is entirely offset by the extra weight of safety/electronic systems. That's why mpg or power/weight hasn't really improved.

Re: Increase in engine sizes
 

seems to me like bike manufacturers put most of the heavy performance sapping crap they need to meet emissions regs etc in the exhaust system. So you can buy a new bike, which might be greener but no faster than the old model, then replace the exhaust system to save 10Kg and gain ten HP. (well okay not on the sv, but these figures are easily achievable with a new exhaust on a FZ1 for example.)

Re: Increase in engine sizes
 

Do any bikes on the current markey use cats?
I cant see the emissions on a bike being so bad they need one really..
Well only a two-stroke!

Steve

Re: Increase in engine sizes
 

mine has 2 cats - one in the header pipes and a huge heavy one in the can.

Re: Increase in engine sizes
 

Bikes are really really dirty to be honest. Many bikes allow fuel to run into the engine on the over-run, which is essentially wasted fuel (but allows a smoother transition from shut throttle to partialy open). If you consider also an SV650 can do 55 mpg on a really good day, and a small car (polo or something) can get as much on a good day, but has a bigger engine, you see that cars are quite ahead.

Some bikes (I think BMW's?) have some clever electronic trickery that means the fueling is run in sich a manner that its almost running lean, but not lean enough to cause self-destruction.

Re: Increase in engine sizes
 

I can get 70mpg out of it! 210 miles on 15 litres :thumbsup:

Comparing the emissions, it'd be interesting to view the comparison including:

• Lack of time sitting with engine running in traffic jams
• Total emissions created during manufacture

I think if the government are going to be serious about emissions, they need to be serious about all of the contributing factors.

Re: Increase in engine sizes
 

When manufacturers add cc's it tends to be to keep the previous models power whilst keeping to the latest emissions laws, on a bike you just dump the exhaust and take advantage of the extra cc's more easily than on a car.