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Hi everybody, could any body advise me on what would be the correct settings for the mixture screws on the bottom of carbs ? My bike is 1998 R1 i need to set them as they were turned by me! After changing the engine and not being able to get it to tick over. It wouldnt even after i balanced carbs. The idle screw would allow it but this was purely bringing out of idle. I have now turned all four screws completely in. Then turned each one out a turn and half. This is better but it wont easily start when hot.
Thanks in advance if any body could advise me.
Ime no mechanic but i am fairly compedent around mechanical stuff.

Thanks
Melv

Welcome in Melv

Quick tip , get a Haynes manual [emoji38]

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Hi. Thankyou for your reply. This is very helpfull. I do have pdf download now.
Maybe you could tell me whats needed if you can please.

What my manual says is 2 half. Turns for 98 model.

But the problem is i have fitted engine from 2001 model. I see that the settings for are just over 3! Does this mean that i need the carbs off later engine or are they the same? Also my engine never had this vacuum setup either so dont know exactly where they go.

Thanks mate

Hi. Thankyou for your reply. This is very helpfull. I do have pdf download now.
Maybe you could tell me whats needed if you can please.

What my manual says is 2 half. Turns for 98 model.

But the problem is i have fitted engine from 2001 e

Stick with the later carbs and go 3 and a quarter turns as in the manual

I think it's 2.5 turns with the #17.5 pilot jets on the early bikes and 3.5 turns with #15 pilots on the later ones. They run better with the #15 pilots.

Ffs read the post about the 2001 engine wrong and thought he had the later carbs too !
Later carbs with 15 pilot jets are better in my opinion due to the midrange . So 2 and a quarter turns for your 98 carbs IF they have 17.5 pilot jets but do check them as some people say some of the later 4xvs had 15 pilot jets

Worth buying a set of 15s IMO [emoji6]

newsh wrote:Worth buying a set of 15s IMO [emoji6]

+1

Ok thanks .

I have the 4xvcarbs from my R reg R1 so i have put them on to 2001 engine which i fitted as my 4xv went bang . Chain snapped!. I have now set the carbs at 2 ,1'2 turns just dont seem like it wants to go top end or its struggling. It went like hell before wish i had bought another 98 engine.

[quote="98R1Wardy"]Ok thanks .

I have the 4xvcarbs from my R reg R1 so i have put them on to 2001 engine which i fitted as my 4xv went bang . Chain snapped!. I have now set the carbs at 2 ,1'2 turns just dont seem like it wants to go top end or its struggling. It went like hell before wish i had bought another 98 engine.
My 4xv motor blew and i had a 5jj fitted with the 5jj carbs and the only difference i noticed was the extra midrange which calmed the 8-9000rpm hit slightly , after a blonde moment with the 5jj carbs i fitted the 4xv carbs , the extra midrange was gone it it ran exactly like i remember the 4xv running !
Was your 4xv motor STD or tuned ? Is the 5jj motor STD or tuned ? Have you tested the compression on the 5jj motor ? Is the Exup valve working properly ? Have the carb rubbers been seated properly ?
Hope you get this sorted bud , keep with it .

Hi matey . Sorry late reply. Ive sorted the carb problem now thanks for your advice.


However i now have another issue the bastard 5jj is using half of litre of oil every time i been out on it! Like i said only just bought this engine! Runs like a dream pulls fantastic. So is this likely to be rings? Or stem seals? I have my 4xv head which is completely rebuilt. Will this be worth a try before pulling motor apart? Also is their any way of removing this vaccum system that i assume is for emissions? My 4xv doesnt have this?

Thanks

The R1 engine has been known to use a bit of oil , it's a 50/50 thing where some bikes do some don't .
As for the A.I.S removal , search and you shall find . . . . . . . Eventually
viewtopic.php?f=48&t=13801

That's a lot of oil! I expect it's blowing smoke?

If it is smoking, then get someone to follow you and see when it smokes. Under power it's rings, closed throttle is valve seals.

It won't run any better with the AIS removed.

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