Happy new year ,and the suns out

fred · Post by **fred** » Mon Sep 17, 2012 10:02 pm

ile ask about this ,ive read this about rd jets ,is there any visuual difference ?or do they just flow less ? ,i can measure the jets on a smartscope at my mates and have the sizes from here http://www.allensperformance.co.uk/jetsizeconv.html , ime going to buy some more jets friday ,n rebooked mot for 4,, running on the 160`s yesterday the engine was bogging down at 6 thou

dave32 · Post by **dave32** » Mon Sep 17, 2012 11:29 pm

size wise they maybe the same,but the shape around the exit has a big effect so yes they may measure the same but if they were put on a flow bench its much less.
Not something that would make much sense if you went bigger and it went bang after running ok on smaller number jets.
This was discovered by the late Dr John Robinson of PB fame whilst setting up a SS400 spec KR1s racer.
you can run the RD but bear in mind how far you need to go in size to be just up slightly on the genuine in terms of flow (i currently run RD155's),just dont swap between the 2 (keihin and RD).
if its "bogging down" at 6000rpm its more likely to be the needle as you wouldnt be at a wide throttle opening at this low revs.
i always use the term "bogging" to describe a LEAN mixture,if its too RICH(on the needle) it will splutter and cough then "clear out".
whats it like above and below 6000?
What needle and position are you using?

fred · Post by **fred** » Tue Sep 18, 2012 9:28 pm

standard needle middle clip from memmory ,ile lift the needle tommoro n try it with several sets of plugs ,new + clean dry used ones and see what its like.
ile keep the info here.

run this evening ,160`s bottom clip position, crackling & not pulling after 6 grand ,glossy plug and silencer ,choke had no effect ,

wont be able to test again till next week as me mums badly,need to buy more jets this weekend

fred · Post by **fred** » Thu Sep 20, 2012 6:49 pm

hi dave ,cheers for the info ,brought my eye glass home had a look and there RD jets ,so will have another go early next week hopefully ,

dave32 · Post by **dave32** » Thu Sep 20, 2012 11:53 pm

Hi Fred,no worries,
dont pay too much attention to plug colour or silencer outlet cleanliness at the moment.
Sounds WAY too rich if its crackling and wont clear,i take it you mean the needle clips in the "highest position" when the needles in its operating position,i.e the needle is sitting further down inside the needle jet/nozzle,so its as lean as it can go?
With an unknown tune and one off pipes its probably better to put the needle in the middle clip and just come down on the main 1 at a time until it will pull into the power,then set the needle.
If you start off way too lean or rich on the needle it can confuse things as it will effect the main,what you put in has an effect on the next (needle to main).
Let us know how you get on

Hope your mothers better soon,
ATB
Dave

fred · Post by **fred** » Sat Sep 29, 2012 7:28 pm

had a good day ,and thought why do i take the carbs of the airbox ,as ive done the removable top spar mod,work a treat ,and welded up some stainless steel long T bar for all the allen bolts,much quicker.

today ran :-
1) 157.5 bottom clip ,then top ,,,,got improvement,
2) 155 bottom clip rich doing choke check ,,middle clip ,no change as such on choke ,pulls good feels like its being held back,top clip pulls good starts to run rich on choke
3) 152.5 bottom clip pulls clean starts to run rich on choke feels like its being held back
4)152.5 middle ,changed plugs ,pulls well ,seems a bit weak 9 to 10 grand
will clean all 5 sets of plugs tommoro ,go back to 155 and bottom clip,
is the airbox restrictive

all ive done is drill 5 13mm holes in the front ,running 0.8mm stainless steel mesh and scotch bright as a filter (i am skint) quite happy tho ,hope everyones well n good and had a good one

dmac · Post by **dmac** » Sat Sep 29, 2012 8:36 pm

No wonder you are having trouble mate, your carbies are on upside down

fred · Post by **fred** » Sat Sep 29, 2012 8:42 pm

ha ha good one

, just realized i have got some standard pipes ,ile get some caustic and dose em up ,would be interesting to see how it feels

fred · Post by **fred** » Mon Oct 01, 2012 7:27 pm

put (rd) jets back to 155 and 2nd from top clip ,and took it for mot ,pulls cleanly to 11,000 (the pistons and rings have done 1000miles odd but didnt want to strain awt) passed mot

. and now am on peter hammonds list for doing nitrogen regassing at £5 a time $\:D/$

dave32 · Post by **dave32** » Wed Oct 03, 2012 2:56 pm

Thats good news!

Airbox wise,heres my thoughts,
the only restriction is too keep the noise down(all road bikes have some form of this),what i do is remove the REAR half of the lid,bear in mind noise is increased quite alot and you need to upjet a size at least when doing this.
What i found when doing this mod is the engine would rev harder in the power and would pull the next gear easier( i tried it back to back with the Full lid and jetted to suit).
You can get proper airfilter foam off ebay cheap,and cut it to sizemso no excuse for not using it

Seeing as its turned a bit colder i would keep an eye on how its running as if it pulls cleanly now it may be spot on but could be too weak in the cooler conditions.
Does it pull the higher gears ok at the moment?
Usually when its a bit weak it will be good in the lower gears but struggle in the higher gears (more load).
Also dont aim for a "clean from the outset" mixture,what i mean is if you fire it up and it feels very responsive and revs CLEANLY the first time you open it up it will be too lean when under more load for a longer period of time.
Im not saying you dont want it to rev cleanly but after pottering through towns or traffic its best (safer) to have it so it "clears itself out" when its given a blast again.
A richer mixture may not give as much peak power as a spot on one but it will still put out good power for long periods.
HTH
ATB
Dave

fred · Post by **fred** » Wed Oct 03, 2012 7:22 pm

yea that does make sence,ime going to run on the slightly rich side as i want to do a few miles,its 150 to me dads

Garry · Post by **Garry** » Wed Oct 03, 2012 8:19 pm

After 150 miles on a KR you will probably wish it was a one way

trip

fred · Post by **fred** » Fri Oct 05, 2012 7:40 pm

be alright,may be better than the srx400,fag n coffie stop at donnington services aboot half way ,taxed today ,so off to me bruvs tommoz to pick up some sausages the b4425 is a sound road

dave32 · Post by **dave32** » Mon Oct 08, 2012 7:20 pm

kr's are fine on long runs,more comfy than most 250's/400 race reps.
i used to travel from london to plymouth regularly,over 250miles each way.

fred · Post by **fred** » Sat Oct 20, 2012 2:12 am

the more you do it the better ,it`s good 155 top notch ,i havent got a pen ,wet

KR-1S.co.uk Forum

Happy new year ,and the suns out

mot`d today