First off a disclaimer. This was an independant test of various bits for the KR, the results are for the day in question and the bike in a particular state of tune (+ oddities on the day). The various bits may have behaved differently if the state of tune had been optimised for them, e.g. the jetting, equally they may behave differently on other bikes. As such I am not saying that on your bike these parts won't work and I am making no recommendation as to what is good or bad. Simply reporting what we found with enough background for you to make your own decision.

The Dyno - For this test rather than go south to DynoTech in Basingstoke or Road'n'Track at Aylesbury (the dynos I have used before and can recommend) we decided to try R&S Performance up in Worksop (01909 482670). Sean Webster who runs the dyno has previously supported the LC series that Derby Phoenix ran and he helps out at club meets etc. So as I had heard good things we decided time to go North. Bikes under test were mine, Paul Porter's (ex-Mark Elkington) minus Gibsons and running the barrels of Dave Page's old bike - more on this later, and Andy Blundell's KR1.

The Day - Up at six finished putting the KR back together and loaded it up in the bus. Hitched Andy's bike onto the bus then headed over to pick Paul's bike up. Andy had kindly lent us his trailer so all three bikes + four of us in the the bus (Rock and Paul Lewis were coming along to help). Tuesday night Paul had got his KR sorted he replaced the clutch and cover (Bike looked good but was suffering from age related symptoms so we have had to replace a fair few bits to get it upto scratch). 7:30 head North from Paul's place eventually getting to Worksop at 9:30 bang on time. Ten minutes trying to find the dyno on a large industrial estate - drove straight past. Then we are away. Rain on the way up has cleared and we have blue skies though there are plenty of black clouds hovering about. First up Paul's bike and this is how it went....

The state of tune - of the various bikes is as follows
Mark J - KR-1S - 26J TZ pistons, MJ barrels re-worked by Graham File (quite a bit different to standard barrels), standard pipes, ram air (though no big fan on the dyno so this should do nothing) 28 mm carbs, standard reeds - no work done on the crankcases or reed blocks, 50/50 fuel (Doesn't actually tell you much). Standard crankcases
Paul Porters - KR1 - 3TC TZ pistons (requires shortened barrels), File barrels, standard pipes, half a ram air system fitted (haven't finished making the other bits) 28mm carbs with KR-1S needle 135 main jet, 50/50 fuel. rest as above.
Andy B - KR1 - 26J TZ pistons - MJ old head, ram air system, KR1 28mm carbs 137 RD jets, Nikon expansion - rest standard KR1.

What we Tested - Exhausts were tried on Andy's bike. Carbs on my bike, reeds and airbox on Paul's bike.
Exhausts - Nikon and Standard KR-1S. We had hoped to test the Gibson's having had them repaired by Tony Green, but the mounting stubs were down with Graham on Paul's barrels that were down being welded. Shortening the barrels to run TZ pistons other than the 26J (they use standard barrels) weakens the barrels and they can crack if you are not carefull. Check Mark Brown's dyno runs for Micron Pipes and I have previously run the Huxley's.
Black Boxes - I can't tell the difference between a KR1 black box and a KR-1S (Part Nos KR1 have 1234 in numbers KR-1S 2789 in numbers. A KR1 ignition opens and closes power valves quickly when you turn ignition on. A KR-1S opens them waits a few seconds and then closes them). So we tested 5 back to back. Mine (KR-1S), Paul's (KR1), a spare (KR-1S), Dave Page's (KR-1S) and one off a bike we bought Saturday (KR1).
Reeds - Standard, Hy-Tech, Boysen 2 stage, Graham File on special reed block.
Airbox - standard with half ramair, same but with shorter inlet stubs. No airfilter in any bike. Ram air systems like the one in the piccies in the KR tuning bit.
Stuffers - standard, modified 1 and modified 2

The Weather - We had quite a change over the day. Started at about 9 degrees and went up to 12 degrees with a few dips during the hail and rain. Humidity went from 47% to 65% and bounced around a bit in between. Air pressure started at 985mB dropped to 975 then climbed back to 983mB. Not ideal conditions for testing as the changes could mask a 1 hp increase. However over the 10 to 15 minutes between tests

The Testing - For each run Sean first warmed the bike up to 55 C then did the first run. He would then do three runs after that starting the run at 8000 and knocking off at 11000. Usually the first run would give a couple more horse mid range than the next 3, top end tended to be down a bit, possibly something to do with exhaust or crankcase temperature. The three would be fairly close. For comparisons we took the first of the group of 3 where we could get a run. Where we couldn't we took the best run we could get. The temperature was up to about 65 C at the end of the runs. We had a gap of about 10 minutes between groups of runs as we swopped bits over. Results are STD the software correct for air-pressure. So if you read 53 hp and the air pressure is low (such as we had) it then multiplies the result by a correction factor on the day this was 1.02. Didn't know Dyno's did this so next time you are down ask what you are seeing. On a high pressure day the correction should take the power down.

That is it for Part 1 - I am working on the next bit which should appear soon.

Part II - Reeds Part III - Blackboxes Part IV - Exhausts Part V - Airbox Part VI - Carbs

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Material Copyright © 2002 Mark Jordan