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Gemi chip results and question about air inlet tube

hillbillync

New member
1994 R1100RS
Installed the 12k Gemi chip yesterday (along with fresh TB balance at low/high rpms) and man what a difference! Lots more pull and so much smoother during low rpm cruising. I've only got a little over 2000 miles on the new to me bike but never had the surging problem I've read about. I had already switched to the Autolite plugs and installed a set of the newer fuel injectors but the chip was icing on the cake. I told John I was going to be installing a K&N (did that before chip arrived) and installing a set of longer GS manifold tubes (not arrived yet, USPS sucks). Maybe the GS tubes will add a little mid-range.

The question I had was about the fresh air intake before the air box. Just saw a FB post where someone trimmed a section of the inlet out to increase the opening. Haven't ran across this yet in the past year's reading. Any one have experience doing this or at least 2nd/3rd hand knowledge of it? Seems cheap & easy to try?

inlet.png
 
I had a San Jose air intake system on my R1100S with the K&N filter. It has a much bigger diameter inlet opening than the stock OEM intake. My body work and fork tubes were hitting it preventing them from functioning as designed. So I put the OEM stock system back on to correct the problems. I didn't feel any performance gain or loss. I did keep the K&N filter and I do have the performance chip from Austria ( https://www.ebay.com/itm/3344767684...bXK0roDpE0l-Gg6lJcGpOalGWEzFvMq4aAtw7EALw_wcB. )
The chip made the bike run much better at all RPM,s, it had an older performance chip from I think San Jose BMW which felt sluggish at low RPM's.
Just returned from three track days at the Ridge (Washington) and took in MotoAmerica weekend. My R1100S the second day lost top end power. Problem turned out to be a bad Coil Stick, replacing both and a set of new plugs really seemed to make the thing pull better.A_Racers_Days_June_27_2022_Ridge-1226.jpg
 
First post.

I Don't have an RS but I can tell you about my R.

I have a 95 R1100R, and I removed the tube entirely. I suspect the tube is there mainly for intake noise suppression, not performance. Anyways, I never had a good butt dyno so I am not sensitive enough to notice a difference in performance with or without it, but the bike sounds much much louder and that I can notice.


Edit; The R bikes has a different intake tube then the others so YMMV.
 
Intake tubes are very much a part of the engineering of an engine's power-making characteristics, as they are the first control of airflow. Changing the length and/or diameter does make a difference (similar to tuning the exhaust for certain characteristics besides sound).
Two oilheads ago, I put the GS tubes on my '97 1100RT, and the difference was very much seat-of-the-pants noticeable, not a "lot", but there.
And motorcycles are definitely not the only engines/manufacturers that incorporate different intake setups into their designs.
 
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