| Archive for KAWASAKI KH & S SERIES FORUM The only forum in the world dedicated to the KH & S Series Kawasaki triples |
| dandare |
Go faster.I working on a kh250 motor to do some drag racing this year, what are some good mods to make with out spending to much Cash, any info will be worth many beers when we meet up. (yes i know about loosing wieght) :D :lol: |
||||
| 180kid |
have some porting specs from an old mag, but on my old comp.,
will drag em' up for ya,...Brian. cant really do much with stock motor on 250's,...perhaps 1/2sec with carbs and pipes,,,other than that will need major work x 3 cyls..dont come cheap, |
||||
| 180kid |
|
||||
| g6mow |
http://www.kawasakitripleparts.com/MAGAZINE-ARTICLES | ||||
| dandare |
I do remember reading that artical, crap pipe to start with. I read recently about taking out gasgits or double up on the base, what about cutting the skirts on the rear of the piston and drilling the carb slides, ?. :thumright: | ||||
| mark |
tuninghi dan,i still remember the lift you gave to us kent boys in your van at northern a couple of years ago and laugh to myself!! anyway,for dragging not road use you need to be drastic ,lose most if not all bottom and mid range power,to increase top revs and power significantly.so i would p.m u some secrets if u like!!! :twisted: |
||||
| kas750 |
I think we would all be interested in that Mark.Why not post it for us all :D | ||||
| mark |
go fasterhttp://uk.youtube.com/watch?v=I4gtxcepLtU |
||||
| 180kid |
well held that man...!!
looked like a flip for sure,... :lol: |
||||
| 650hardtail |
wouldnt the best performance mod be a 350 top end??? | ||||
| g6mow |
Then it would not be a 250 :D |
||||
| dandare |
Need to keep to a 250 but, I'll take all the help i can get. I think the competion will be strong, got to have a edge. what about gearing? standard or ? send me your secrets and tips :lol: |
||||
| simonh |
cheapest way is 1mm lifters, then get barrel tops lapped back 1mm
then lift the exhaust and drop the inlet somemore. fit 400 carbs and inlets (i can lend you a set if you aint got any) and pipes and filters set the timing for superhot melty pistons and back off a tadge pistons are fookall, go for it dan instead of lapping the barrels you could run with out head gaskets, but it would take forever to seal them and then they will blow straight away. |
||||
| tony_d123 |
I lapped my 250 heads straight onto the barrels + extra base gasket. 2 days with valve grinding paste and it sealed perfectly never leaked at all.
I went down 2 teeth on the back and it would still rev out in top given a long enough run but for sprinting I would think you need to be looking at losing at least 1 or 2 teeth on the front and as big as you can get on the back? |
||||
| 180kid |
yeah what is the sprinting class this yr,
thinks, 250 in there own class and 350 /400 together, not heard anything yet, either way, |
||||
| simonh |
thats why i wasnt reccomending it tony, i did a similar apprenticeship on my 350 lc :shock: |
||||
| dandare |
When u say 1mm lifters, extra base gaskets?, and then cut the top of the exhaust port and lower the bottom of the inltet port is that right ? can i rejet the 250 carbs, i was'nt going to run filters. and is lapped a posh word for cut away or grind ? im from the valley's mun :wink: |
||||
| tony_d123 |
"lapping" is mating the surfaces so well that they seal without a gasket, like grinding or lapping valves into the seats.
I did it with a loose bolt thro' each stud hole in the head into the barrel stud hole, and you can then rotate it a few degrees each way. You put fine valve grinding paste onto the mating surface then just keep twisting it back and forth......for days! You can tell when they are perfectly matched as you get an even spread of paste all over the surface. You obviously have to make sure that you never mix the heads and barrels. |
||||
| 180kid |
who from.... :? |
||||
| mark |
ripperdan,check your p.ms .and there will be a kh250 singing in the valleys!!!!!!!! |
||||
| 180kid |
Re: ripper
you sound like one of them southerners,...! :? |
||||
| dandare |
180kid wrote:
who from.... :?[/quote] Malc Anderson is putting to gether a 250 to sprint,( got to whip his arse) and you could race your lads bike, a few lads from this board could get a bike sorted. Does'n t get any cheaper. |
||||
| 180kid |
Malc Anderson is putting to gether a 250 to sprint,( got to whip his arse) and you could race your lads bike, a few lads from this board could get a bike sorted. Does'n t get any cheaper.[/quote] you mean the S1c?, be a good laugh Dan with the 250s, but ours aint really competative, only got allspeeds,.and mr lightweight, and we just done the 350 for this yr,. 400's unbelievably zippy too,..wont be racing the 750, perhaps just for one meet to see what it does over the quarter,... :P |
||||
| yogi20 |
can i rejet the 250 carbs, i was'nt going to run filters. and is lapped a posh word for cut away or grind ? im from the valley's mun :wink:[/quote]
Dan you will need bigger carbs OR you won't realise those horses you want .........imho |
||||
| malc87 |
finally got me 250 drag bike motor ready :shock:
|
||||
| malc87 |
and more :D
|
||||
| simonh |
is that a wind up malc :?: looks cool anyway 8) | ||||
| ståle |
I recognize that engine :wink: | ||||
| simonh |
nice carpet :shock: | ||||
| 180kid |
Hey, that looks like my engine !,...except mines rubber mounted and running pump,..
defo old pics, from an old thread :roll: :lol: nice one Malc,. |
||||
| malc87 |
im only showing you the "OLD" pictures because i dont want you to see the new water cooled barrels :shock: :D | ||||
| dandare |
Dan you will need bigger carbs OR you won't realise those horses you want .........imho[/quote] All sorted Carl. I'm waiting on the heads and barols and it's will all go. |
||||
| simonh |
post some pics then dan 8) | ||||
| dandare |
Do I run the oil pump or not? If I do will it rob me of power? any feed back will be apreciated. :D | ||||
| simonh |
If you can work out the oil to gas ratio better than the oilpump then yes, you will get marginally more power if you get the mix right, or less if you get it wrong :shock: |
||||
| dandare |
Cheers Si. sod it I'll run the pump, and dont have any breakfast before I race :oops: | ||||
| The Wolfman |
Mechanically the pump will rob the engine of bugger all power. for the complications of calculating every single charge of fuel in the tank I'd just go with the pump too.
Only cos I can't add up tho. :D |
||||
| simonh |
another point if you dont run the pump, if you go on reserve the engine will sieze instantly, no warning | ||||
| husson73 |
G6mov, just thought to order a new ship of 250 pistons, seems Dan would be one of regular customer :lol: :lol: :lol: | ||||
| simonh |
|
||||
| g6mow |
:thumright: :thumright: :thumright: :D :D :D :D :D |
||||
| dandare |
Not my my week end. Got the 250 sprint bike together, battery, fuel, check all wire conections and It will not fire up, Iwill check the coils
tomorow, sould i have power at one side of the coil or not with the ingnison on ? |
||||
| simonh |
only when the points open/close, easier to check there mate | ||||
| scouse |
if you can find some instant gasket called omnivisk (german) you can use that instead of head gaskets. clean the heads and barrels torque them down and leave it to set for a few hrs we used it at collage, I did my 500 heads and I had to prise the heads and barrels apart with a jemmy really really good stuff Gary T |
||||
| 2smoke |
Re: Go faster.
Hi dan 250s are all about power to weight,loosing 2 stone is =£1000 of tuneing  .
cheap way for more power bore it to maximum over size,set of bellmouths 400 carbs ,set of chambers,polish the heads with solvol ,knife edge the inlets and polish all the ports with dremel.you can still run head gasgets.use shell v power .if you cant afford carbs put big jets in,if you cant afford chambers, chop the first section of the baffels off,loose weight,
and slightly over gear,you loose a bit at initial take off but gain at the end of the drag strip. 
|
||||
| dandare |
well guys I had a cracking time on the 250 it wasn't performing all that well. it would not rev out,  main jets to small but ill change that soon. also still needs more porting. but still had a good time with all the lads. ran a 13.6 on the kh750 with a slipping clutch  best time on the 250 was 17.4 but it will get better. whatch this space
|
||||
| simonh |
what pipes you running dan? | ||||
| dandare |
I was running alspeeds, not the best, all ive got. I did swap the ones of my 750 bit more volume and longer seemed crisper. | ||||
| dandare |
Spannies for 250anydody got a set of spannie that work for my 250 drag bike,
|
||||
| simonh |
you need dencos dan mate | ||||
| dandare |
Yep, Like rocking horse poo, see you at the northern
|
||||
| dandare |
Had an other go on last Saturday ran a 15.3 @83 mph, well pleased. getting faster. will be better with some tidy pipes. 
|
||||
| 180kid |
is the top end better with bigger mains ?,,.
|
||||
| dandare |
Yes Brian, I may go a bit bigger. and i will try the pipes off the 350 a well, I need and other 5-10 mph to beat steve  ,I will try and race in August Hope to run the 350 as well, can't wait 
|
||||
| ringadingdingdingdingding |
I've always found that unburnt fuel is a problem. If you can solve this you will gain a good 2-5 mph
|
||||