Suzuki GS400 20 to 26kW

[Guest]

Hi,my Suzuki GS400 is a german model with 20kW to unleash the 26kW is enough to change the camshaft from another market or i need other modifications?
Thanks

[Ecklund]

Hi,my Suzuki GS400 is a german model with 20kW to unleash the 26kW is enough to change the camshaft from another market or i need other modifications?
Thanks

Hello Mr. Andy,

I think you will find that the kW scale is not well known in north America. However, may I suggest that there are many threads on increasing the power of the Suzuki twin. Experiment with various words in the 'search' function on the forum site.

Changing the cam alone at best may move the power band of the motor but will likely result in lower overall and disappointing performance. Perhaps the heads on the Suzuki twin will benefit/tolerate a cam upgrade but I doubt it. Your search in the forum threads and on other Suzuki twin sites would confirm this for you.

Improving the air flow into the engine and the exhaust out of the engine with a high flow air filter and performance exhaust MAY make a hotter cam worth the expense and effort. The twin guys would know better. But then you must be prepared to take the time and effort to reject the carbs to deliver the correct amount of fuel.

My bike came with an aftermarket exhaust and was clearly not jetted correctly as it ran poorly. I replaced the exhaust with the same new version and added air pod filters. Fortunately for my bike there is a dedicated jetting system readily available for just those modifications. Even with that the bike needed additional changes to the pilot jets.

In your case making those changes AND changing the cam would require carb mods and you may on your own to get it right.

Welcome to the site. Please do spend some time and research past threads. Most times you will find someone has already asked about the questions you may have.

Also there is an excellent section on getting your bike back up to factory baseline performance. Which is probably a good requisite for making any modifications.

[Grimly]

Worth checking the simple things first - to restrict for some markets or licencing categories, the models were often restricted by limiting the carb lift internally or putting a simple restrictor plate in the intake port.

[Andy24]

i checked the carb lift all the way and there no restrictor plate on the intake,i read that for german market the power was restricted by camshaft modification,and i wanna know if someone know or have done the modification to derestrict the bike or if its worth to derestrict the engine with other camshafts? is the engine more reliable with 20kW or 26kW? is maybe a better choice to change the air filters(some more open),a better exhaust and rejjet the carbs?
Till recently i rode a Kymco zing 125 so i dont care about speed 20kW is enough for me now,i care more about reliability because im gonna do many trips.

[Old guy]

I would swap the cams and make follow whatever jetting matches the unrestricted bike. Reliability shouldn't be an issue, the bike was designed to make the full power.

[tkent02]

What he said, but do a litlle research. Are they actually different cams or is just the cam timing altered? Did they change anything in the caburetion? Perhaps slides raising at a different rate, different jetting or anything. Sometimes they alter the ignition timing, or limit the RPM, could be they used restrictions in the exhaust as well.


I'd find out which they used an fix them all before doing any new mods to anything else on the bike.
One thing is that all of these reduced power output bikes will have written decryption and instructions for reversing it all to the original 26kw configuration.

[posplayr]

745 Watts per Hp

20KW==>26.8Hp
26KW==>34.9Hp

http://www.rapidtables.com/convert/power/kw-to-hp.htm

[JEEPRUSTY]

a massive increase my goodness

[Ecklund]

745 Watts per Hp

20KW==>26.8Hp
26KW==>34.9Hp


http://www.rapidtables.com/convert/power/kw-to-hp.htm

And that's how they list a vehicle for sale. Pretty sure its the way they tax the vehicle.

[tkent02]

a massive increase my goodness

30% is massive. Especially on a smaller engine.

[GregT]

30% is massive. Especially on a smaller engine.

Did you know that Harley marketed a 20Kw restricted version for specific Euro markets ? Absurd....

[tkent02]

Nothing absurd about making new riders stay on less powerful machines for a while. Although if I had to ride a 20KW bike, I sure would't choose one that weighs 800 lbs.

[pete]

I'm not 100% certain but I seem to recall from the factory manual that there were differences listed for the 450's for the German market.

One of those *may* have been altered cam timing but I can't recall exactly off the top of my head.

I will try to remember to have a look at the manual today.

Most things like that are fairly common between the 400 and 450 so it should be fairly easy to confirm...