lots and lots of questions

[mrlogix]

I want to start out saying that if these questions have already been addressed in the forum, sorry, I am reading the older posts as fast as I can. I'm very interested in purchasing a Buell 1125R/CR next spring/summer. On to the questions,
1. The listed compression ratio is 13.3-1 for the 1125. That seems awfully high to me for the street. Do you experience a lot of problems with streetability in the summer? Overheating, ping, knocking, etc., etc.
2. Who can afford the new 1190RS? Has anyone tried to update the 1125 engine to the 1190 spec? I know that they didn't get 30 hp out of a 3mm bore change. I seen the post referencing that the injectors was the same, which means there is an ECM flash upgrade, but what about cams, head porting, valve sizes, etc., etc.

I have a lot more questions, but will wait until later to keep from typing all day (I program robots, plc's, vision systems and still can't type) thanks in advance for your time and comments

 

[Mike Van V]

Question #1 -
No, not at all.
Remember that detonation can be controled by a proper chamber shape. Rotax has done this. By the use of a small volume, pent roof chamber vs. piston diameter.
Rather than use giant, odd shaped chambers like the old Chevys, Fords and Chryslers (remember that the Rotax engine has a 4.055" diameter bore) and filling them with odd shaped domed pistons to get the compression, Rotax uses a small shallow, cleanly shaped chamber.
Also remember that using an aluminum head, normally a full point in compression can be added vs. an iron head.
AND...the use of a good fuel injector system also has a lot to do with being able to go that high in compression.
The American and most offshore car engines still don't use "port" injectors like the Rotax engine (most bike) does.
All these things add up.

As far as being able to afford an 1190...not me...!

Mike

 

[mrlogix]

any idea what the fuel injector lbs/hr rating is for a stock 1125R? I was on a couple of websites earlier today, and one of them had a review of the 1190RR (I know, race only). It stated that the 1190RR had two (2) injectors with 'Shower Heads' instead of the single injector of the 1125RR. It didn't state the injector lbs/hour rating was of the 1190RR, but I got the impression that it was the same model as the single injector.[confused]

 

[mrlogix]

Rotax uses a small shallow, cleanly shaped chamber.

is this using flat top pistons or a shallow dome? anybody know the combustion chamber volume? Quench area? I know this is a lot of questions (hence the subject line) but my intention is to buy a 1125R next spring and then convert it to the 1190 spec the following winter.

 

[tyler]

you can buy a ktm rc8r for 20,000 new ready to race 175rwhp don't do it. that's a pipe dream for a lot of people..after haveing mine for a year i should have bought a differnt v-twin....

 

[mrlogix]

yeah, but getting there by a different path is half the fun

 

[xtremelow]

Seen someone post this up in the picture library the other day. Comes in very handy.

 

[Kid1620]

Lol now that is funny ^^ people should open their eyes a little more.

 

[mrlogix]

I found the search function. Direct and to the point, but I am also having a lot of fun searching the older posts one by one. I'm getting to learn the forum and personalities here, and a good hard laugh no and then. Some of the replies are hilarious. I work a high stress job and need the laughs.
Thanks

 

[albert666]

when i bought my 1125 the first i didn't think was its got a high compression ratio
no i can't afford an 1190 either
plus i'd buy one before next year if i were you, they'll have all broken down by then

 

[tyler]

I would say a KTM RC8 IS A VERY DIFFERENT PATH......[cool][cool] BUELL1125R[sad]