kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 16, 2021 13:14:12 GMT 1
Hi, 28mm keihin flat slides,oil pump and standard throttle. At present doesn't open carbs fully. Is there a simple solution ? Im assuming i will need a different twist grip and bar switch set up to open carbs fully but then if carbs and oil pump are connected as present on a 3 way link it would try to pull pump further than it's set up for. I know others have done this so advice from them would be great,cheers
|
|
|
|
Post by stusco on Jun 16, 2021 14:20:46 GMT 1
You have to alter the adjuster on the carb tops for more adjustments i can’t remember what but one of the black belts will advise you shortly
|
|
|
|
Post by Tobyjugs on Jun 16, 2021 15:24:19 GMT 1
I've noticed this as well.
You really have to pay attention to the Lenght of your outer sheath and free cable.
The reason being the splitter has limited movement. Never measured it but it might be 30mm. Any way if your cables are correct you will have maybe 2mm tolerance for balancing your slides.
I think there are a lot of people out there with 90% full throttle who think they have full throttle which is a waste of the carbs ability.
|
|
|
|
Post by Tobyjugs on Jun 16, 2021 15:26:40 GMT 1
I forgot to add Stusco is one of the black belts.
|
|
|
|
Post by dusty350 on Jun 16, 2021 15:34:10 GMT 1
I did it in my 400 rebuild thread. Not near my pc at the mo, but I trimmed back the outer cable covering to allow the inner cable to reach further into the carb. Allows full lift on the slides. Easy job but the metal spiral of the outer cable is quite tough to cut so go carefully so you don't damage the inner cable
Dusty😉
|
|
|
|
Post by LC_BOTT on Jun 16, 2021 16:25:03 GMT 1
Are you talking about the PWK28's?
|
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 17, 2021 10:55:56 GMT 1
Are you talking about the PWK28's? Yes pkw28s, I made my own longer inner cables to the carbs to allow a fitting to slides. The adjusters are at the lowest point and as soon as I open throttle slides move. The problem is that the 3 way connection does not allow you to pull slides further up, so one solution would be to make this longer to get more movement but that would increase it on the oil pump ! |
|
|
|
Post by Tobyjugs on Jun 17, 2021 11:07:51 GMT 1
Are you talking about the PWK28's? Yes pkw28s, I made my own longer inner cables to the carbs to allow a fitting to slides. The adjusters are at the lowest point and as soon as I open throttle slides move. The problem is that the 3 way connection does not allow you to pull slides further up, so one solution would be to make this longer to get more movement but that would increase it on the oil pump ! If you take a close look at the oil pump you will notice the cam levels out at a certain point, which means you will only get a maximum amount of oil if you twist the throttle further. I'm sure Arrow will read this and fill you in on the finer details of the oil pump operation and adjustment. |
|
|
|
Post by jessy03 on Jun 17, 2021 19:29:43 GMT 1
I think you need to be hitting the top of the cam at half throttle, that’s maximum output I believe, could be wrong though Gary will confirm.
Re - cable fit some 45 degree bends no need to modify the cable or you can fit the bends off your mikunis with a little bit of work.
Jess
|
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 17, 2021 23:44:56 GMT 1
I think you need to be hitting the top of the cam at half throttle, that’s maximum output I believe, could be wrong though Gary will confirm. Re - cable fit some 45 degree bends no need to modify the cable or you can fit the bends off your mikunis with a little bit of work. Jess |
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 17, 2021 23:53:52 GMT 1
No bends fitted, as I've said problem is in order to move the slides further up the carbs I need to pull the cables up further, at present this is restricted by the distance the 3 way connection allows you to pull the carb and oil pump cables,I would like to keep standard twist grip and switch cluster has anyone successfully got round this problem and if they think they have, checked that the slides are fully open ?
|
|
|
|
Post by Tobyjugs on Jun 18, 2021 0:15:38 GMT 1
The twist grip if standard should be ok.
You are mentioning the splitter. I would advise you to remove the throttle cable completely from the bike and measure the travel length of the splitter by marking the cable at fully in and full out on the twist grip side of the cable. If you have 30 mm + you then need to check the two separate carb cables to see if you have the same movement. Once thats checked and found to be good it's only a matter of having the correct length of free wire poking out of the cable ends on carb slide ends (they have to be exactly the same length) and possibly the throttle side. I would check the operation of the carb on the bench by pulling on the twist grip end by hand.
It should be possible as i mentioned before but there is very little room for sloppy tolerances.
|
|
|
|
Post by jessy03 on Jun 18, 2021 6:14:05 GMT 1
Pretty sure you can’t fit a std cable to the pwk’s with out a bend the cable won’t fit. You will need some bends either angle tops from splat shop or modify some mikuni tops or the easiest way fit the lower cables from a KR1.
Got these carbs fitted to two of my bikes with std cable and switchgear.
Jess
|
|
|
|
Post by arrow on Jun 18, 2021 6:29:20 GMT 1
Yes pkw28s, I made my own longer inner cables to the carbs to allow a fitting to slides. The adjusters are at the lowest point and as soon as I open throttle slides move. The problem is that the 3 way connection does not allow you to pull slides further up, so one solution would be to make this longer to get more movement but that would increase it on the oil pump ! If you take a close look at the oil pump you will notice the cam levels out at a certain point, which means you will only get a maximum amount of oil if you twist the throttle further. I'm sure Arrow will read this and fill you in on the finer details of the oil pump operation and adjustment. Quite true about the maximum oiling, but if you can't adjust it out it will over oil in the lower and mid range. |
|
|
|
Post by LC_BOTT on Jun 18, 2021 7:53:30 GMT 1
You've got me all wondering now, haven't checked mine, as not been out on the road with it. Just revved it up on the spot and did some heat cycles.
I went a slightly different route and swapped the KR1s carb cables into the standard splitter. A bit of a downside is they are much longer than LC ones and the spliiter is nearer to the headstock now. But it keeps the standard oil pump control, and no silly adaptors.bends etc.
As I said, not tried it on the road yet, still a load of work to finish first.
|
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 18, 2021 13:30:36 GMT 1
So, i do have bends fitted to to top of carbs, the splitter is standard the outer cables to carbs are standard, the inner cables are custom made longer because the standards were too short. There is NO slack in these. The twist grip is not fitted at present it's all on the bench and I pull the twist grip cable by hand, with the splitter in one piece the slides do not open fully if I remove the splitter cap so that the inner 3 way connector can come out then I can fully open the slides. I would suggest if you have this standard set up then the slides are not fully opening and it may be worth checking. I will check to see how much the cable needs to move in mm on the Pks and compare with the standard carbs in order to get slides fully open and let you know. In the mean time if someone has used a different set up please put me out of my misery, alternatively i may end going back to standard carbs and barrels which will put the whole project back at least another month and several additional pound notes 😖
Cheers for everyone's input too
|
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 18, 2021 14:09:46 GMT 1
Hi again and thanks again for your help, the clues were all there from you guys. Went back to the original cable and compared to the new one and (much swearing here) I found that the inner 3 way connector wasn't going all the way back to the bottom of the tube ( more swearing here) so naturally I wasn't getting the full amount of movement, (huge sigh of relief here) so with some additional twiddling I'm now back on target and will book that track day in August for a spin.
Cheers all
|
|
|
|
Post by Gitram on Jun 18, 2021 19:13:39 GMT 1
nice one.. free fixes are the best..
marti
|
|
|
|
Post by wallcraft on Jun 18, 2021 22:13:48 GMT 1
Another tip is to tap more threads on to the adjusters, right down to the mid bend and a fraction more, enough to get the slides bottoming and able to open max also just enough to sync.
This worked for me with standard cables.
Mark.
|
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 18, 2021 22:28:12 GMT 1
Thanks I'll see if I can get a few more threads
|
|
|
|
Post by Tobyjugs on Jun 19, 2021 9:06:30 GMT 1
Hi again and thanks again for your help, the clues were all there from you guys. Went back to the original cable and compared to the new one and (much swearing here) I found that the inner 3 way connector wasn't going all the way back to the bottom of the tube ( more swearing here) so naturally I wasn't getting the full amount of movement, (huge sigh of relief here) so with some additional twiddling I'm now back on target and will book that track day in August for a spin. Cheers all Just out of interest did you measure the maximum splitter movement once you solved the problem? How many mm was it? |
|
kri101
L plate rider.
Posts: 39
|
Post by kri101 on Jun 19, 2021 11:02:38 GMT 1
Hi it's between 30 and 35 mm
|
|
