More Speed From My 125cc

[shauneyboy]

Hi Guys

Wondering is there any little mods i can do to make my Derbi Terra Adventure just a little bit faster tops out at about 62 mph

maybe boring out the pipe going to the cylinder head or something

cheers

Shaun Riley

[pointblank0]

To be honest mate, probably not worth the effort. You wont get much more out of it and the hassle would be grand. Can you not just get a bigger bike , or are you restricted at the moment?

[mealexme]

You could try getting different sized sprockets to increase top speed but that would mean acceleration would be slower and your speedo may be off

Also you could try just generally lessening the weight of the bike

[Adam]

Get a 2 stoke 125!

[Harrydh3]

push it off a cliff

[Ingah]

Tried giving it a thorough service? I'm deadly serious, much of the things on a comprehensive service will improve the speed a little.

[sliderglider]

opening the exhaust only realy helps on two strokes as you are still restricted by the exhaust valves my advice would be save some cash and pass your test it realy is the best thing i have ever done

[Stu]

I would look at the legal side of it first

If you increase the power does your licence/cbt allow it? if not then you will be riding illegally and void your insurance and not riding according to your licence/cbt

[Boro Jake]

heres what i did, convert two hair driers to 12volt then fix one eitherside to each side of the swing arm, its adds approx 12bhp and 20mph on the max speed

[Bogof]

Hi Guys

Wondering is there any little mods i can do to make my Derbi Terra Adventure just a little bit faster tops out at about 62 mph

maybe boring out the pipe going to the cylinder head or something

cheers

Shaun Riley

 

You could try riding it down big hills...

[Throttled]

If you top out at 62mph that may be down to a faulty or crappy speedo, or the engine needs a service, or you. Are you a big person who wears baggy textiles and sits bolt up right? If so, that is the most likely reason your top speed is not as high as others or expected.

It was the same for me on my YBR. I was the main cause it was not as nippy as it could have been.

[Harrydh3]

also, i can hit 82mph happily and sat up straight on a calm day, but as soon as the wind gets up that plummets, it wasnt pulling over 58mph in 6th the other day

[uk190]

comedy answer.... nitrous and a turbo from a nissan skyline gtsr-r-x-type r-gti

sensible answer.... how many miles has it done? what state are the plugs, air filter and fuel filter in?

derbi claim 15bhp and 70mph for these from new. it wouldnt take much for a little engine to loose a few bhp due to bad state of service consumables and then your top speed will drop off.

if all is in good nick then look at increasing the air/fuel. a high flow air filter and free flowing exhaust will let the engine breathe easier and may increase the power a fraction. however; too much air and you'll weaken the air/fuel mixture and lose power. so you might need to re-jet the carb to provide more fuel and suit the extra air flow.

you'll find a myriad of advice on tuning 4 strokes on the web. the principal is the same regardless of the capacity.

also bear in mind what other said about weight and wind resistance. a bike with little power such as a 125 will be very suseptable to these.

checkin gthe service consumables is dead easy but if any of the tuning info confuses you or seems to complex to attempt (based on your "maybe boring out the pipe going to the cylinder head or something" suggestion) i sugggest you get some help or maybe forget the whole tuning idea and wait until you get a bigger engined bike.