What are StringerStacks variable lenfth velocity stacks?
Modern sportsbikes come with a throttle body and inside the airbox they have throttle body stacks to funnel the air into the throttle body, there are gains to be had there over the stock stacks, for many bikes like the Yamaha R1, R6 etc we sell drop in kits to replace the standard stacks to give more midrange, top end and to improve throttle response, not just on race modified engines, but on stock engines too.
For instance below are some pictures of our R1 kit for the 2015-2019, a similar kit is available for the 2020 onwards R1 and it’s slightly different airbox dimensions. The only parts we re-use from the OEM stacks are the silver metal bars you can see in this picture which just unclip from the stock stacks and fit identically on our Stringer stack kit. The similar (but not quite so good) GTYR kit stacks cost around £2000, our stacks cost just £575 !
What about bikes that don’t have Variable length intake stakes from the factory
Bikes like the Kawasaki ZX10R/RR, CBR600, and CBR1000 Fireblade, and the entire GSXR range of bikes, well they just have lower non-moveable stacks, which some companies will sell you replacements for these plastic stacks, making rather bold claims, but what we have for you is a variable intake kit for your bike, that will (and it’s proven) dramatically improve your motorcycle.
What Stringer Race Stations (SRS) have done is create a kit that is plug and play, it just drops in, plugs into one of your injectors, with a positive terminal to your battery, and you run the wiring either through the AIS/Smog system hole (if you have removed that system) or drill a small hole using the included fitting kit and seal it with the also supplied bung and your bike now has variable length velocity stacks. Yes it really is that simple and even a relatively novice-minded mechanic can have these installed in under an hour.
Once installed and inside the airbox, obviously, this wizardry is all hidden, therefore, so you can be sure the stacks are working we have a green button on the electronic ‘brain’ of the system that you can press to show them activating.
What do they do then ?
At a preset RPM (which we monitor through the injector plug-in) the stacks lift, this changes the profile of the air entering the throttle bodies, giving you more midrange power, they then move again to provide an increase at the upper RPM range, all the time your throttle response is improved by the specially designed and rigorously tested profile of the stacks.
A dyno chart will show part of the story, but it can’t show you the full results, for instance, it shows a gain, but not the full gain as no dyno truly mimics the airflow a bike is in on the road or track, a dyno also cannot display the improved throttle response, you will have to take our word for it and the words of our test pilot one of our customers, Jose.
You can order your Stringer Stacks Variable length stacks here, if you have a bike that is not listed then please contact us, as long as we can get an airbox to prototype a set of stacks we can make them for your bike.