A rant...

[zrpilot]

Sorry everyone but I have a slight rant.

If you are thinking about doing the 450R carb upgrade to your bike please make sure the hot start is properly sealed off. The only way to do this, in my opinion, is to have the stock plunger and spring assembly as provided from Honda in the hot start hole. If you are unsure, replace it.

If you do not do this properly, then you not be able to jet your bike correctly and it will run very poorly.

Also, I will try to help with jetting recommendations as best I can, and in doing so I assume you have done the install correctly. If you have not followed procedures provided by me and others here, please don't blame me for your quad that won't run.

Finally, in my opinion, if your are going to buy a used 450R carb for say $100 or more, why not spend a little more and buy a BRAND new unit from a place like servicehonda.com and avoid potential issues with the used carb?

OK I'm done.

[zrpilot]

The hot start is item number 8 in this picture. You can see that it is a plunger, spring and retaining plug. ALL these things must be in place to inusre the hot start is properly plugged.

[BikeSwimLaugh]

You call that a rant?

This is nothing more then excellent education and a very helpful tip!

Rant-on brother! :D

[justin1022]

ok my friend gave me his old 450r carb off his 2005 450r it was pretty modded so it had a 195 main jet in my quad has a 440 big bore kit 12.5:1 compression hot cam stage 2 hmf pipe heavy duty cam chain rev box stage 2, k&n filter thats it for mods that effect the engine. i put that carb on today right after school and it runs like a beast the torque you gain is insane. i am wondering what jet would you run with my engine set up?i seen in that 450r carb thread that some guy wit a stock engine was running a 203 i believe so i am lost on were to jet this thing.

[zrpilot]

Originally posted by justin1022
ok my friend gave me his old 450r carb off his 2005 450r it was pretty modded so it had a 195 main jet in my quad has a 440 big bore kit 12.5:1 compression hot cam stage 2 hmf pipe heavy duty cam chain rev box stage 2, k&n filter thats it for mods that effect the engine. i put that carb on today right after school and it runs like a beast the torque you gain is insane. i am wondering what jet would you run with my engine set up?i seen in that 450r carb thread that some guy wit a stock engine was running a 203 i believe so i am lost on were to jet this thing.
I say if it starts good, doesn't back fire severly on decel, pulls hard from off idle to the top without and hesitation or bog, leave it alone!! A 195 main is not outta the ball park.

[smokindw]

hey zr we talked bout this and i wanted 2 make sure im right, when i put the other new carb in and i bought the hotstart cable now obviously i dont need 2 plug the hot start plunger but do i have to hook the cable up 2 something or can i just leave it ziptied under the hood??

[zrpilot]

Originally posted by smokindw
hey zr we talked bout this and i wanted 2 make sure im right, when i put the other new carb in and i bought the hotstart cable now obviously i dont need 2 plug the hot start plunger but do i have to hook the cable up 2 something or can i just leave it ziptied under the hood??

Zip tied under the hood is just fine. Again just make sure the cable is not pulled and that the plunger and spring are in the hot start hole.

zrpilot

[smokindw]

thanks and where would be a good place 2 start with the jetting? i know that we have went back and forth bout this many times!! I was thinking on starting on a 200main and working my way down till i dont get any bog but should i put the clip on the 3 or 4th notch down 2 start? and i was going to put a 50 pilot in there and start with 2 turns out on A/F, by the way i bought a motion pro adjusting tool like u have lets just say very helpfull!! i have mains from 165K up to 220K. is the way i described a good way to try 2 jut??

[zrpilot]

Originally posted by smokindw
thanks and where would be a good place 2 start with the jetting? i know that we have went back and forth bout this many times!! I was thinking on starting on a 200main and working my way down till i dont get any bog but should i put the clip on the 3 or 4th notch down 2 start? and i was going to put a 50 pilot in there and start with 2 turns out on A/F, by the way i bought a motion pro adjusting tool like u have lets just say very helpfull!! i have mains from 165K up to 220K. is the way i described a good way to try 2 jut??

Start with the needle on the 4th clip position down. If you can get a decent idle with a 50 pilot and it does not pop badly on decel, then leave the 50 pilot in.
as far as the mains, yes your method described is a great way to do main jet tuning.

Good job!

[smokindw]

thank you but we both know that all the info i know these days came from nagging u!! LOL but anyways one more ? when im testing out the mains do i have to have it warmed up and can i just rip around the yard 2 find out which ones good or should i go 4 a good ride between switching mains?? and i was looking at my stock carb last night and it had a dynojunk kit in it and the main was a 170DJ which is equal to a 190K, now my question 2 u is wouldnt i go bigger than what i had in the stock carb now that i have the 450r or would i go down cuz im getting more fuel and air with the bigger carb thus needing a smaller main compared 2 the stock?? and whit the 170 in the stock it ran really good THANKS ZR

[zrpilot]

Originally posted by smokindw
thank you but we both know that all the info i know these days came from nagging u!! LOL but anyways one more ? when im testing out the mains do i have to have it warmed up and can i just rip around the yard 2 find out which ones good or should i go 4 a good ride between switching mains?? and i was looking at my stock carb last night and it had a dynojunk kit in it and the main was a 170DJ which is equal to a 190K, now my question 2 u is wouldnt i go bigger than what i had in the stock carb now that i have the 450r or would i go down cuz im getting more fuel and air with the bigger carb thus needing a smaller main compared 2 the stock?? and whit the 170 in the stock it ran really good THANKS ZR

You will need to have the motor warm to get the most out of your jetting trials.

As far as comparing one carb (stock) with the 450R carb for jetting numbers, you simply can't do this. They are different carb that have different vacuum signatures, so the jetting does not compare.

[dariusld]

My carb came with a 175 and I thought it was lean. So I went to the dealer and all they had was a 190, nothing in between.So I tried and it was way to rich. I've been to lazy to try anything else, 2 seasons with the 175, but it runs strong and doesn't pop. But unlike everyone else here, I'm not impressed with the gains. It doesn't seem to have the snap of the stock carb.:ermm:

[zrpilot]

Originally posted by dariusld
My carb came with a 175 and I thought it was lean. So I went to the dealer and all they had was a 190, nothing in between.So I tried and it was way to rich. I've been to lazy to try anything else, 2 seasons with the 175, but it runs strong and doesn't pop. But unlike everyone else here, I'm not impressed with the gains. It doesn't seem to have the snap of the stock carb.:ermm: Probably because your too rich?

[dariusld]

Originally posted by zrpilot
Probably because your too rich?

:) No, I said I put the 175 back in. I would be afraid to go any leaner. All the other circuits are pretty close too. I had to up the pilot because it wouldn't idle right. And the needle because it was getting hot. Its at or close to what you have suggested. 175 main , 50 pilot, forgot the screw setting, and 4rth postion if I remember right. I messed with the pilot screw for awhile to get the idle perfect.

[justin1022]

Originally posted by zrpilot
I say if it starts good, doesn't back fire severly on decel, pulls hard from off idle to the top without and hesitation or bog, leave it alone!! A 195 main is not outta the ball park.


ok thanks i am also wondering what do i do with the wires for the electric fuel pump hot start and there is another set of wires to?

[Which 450?]

Originally posted by dariusld
My carb came with a 175 and I thought it was lean. So I went to the dealer and all they had was a 190, nothing in between.So I tried and it was way to rich. I've been to lazy to try anything else, 2 seasons with the 175, but it runs strong and doesn't pop. But unlike everyone else here, I'm not impressed with the gains. It doesn't seem to have the snap of the stock carb.:ermm:

Why do you think its too lean?

[dariusld]

Originally posted by Which 450?
Why do you think its too lean?

When I first got the carb, it came with 175 main and a 48 pilot. I threw it on like that to get a starting point. It idled like caca even when I tried adjusting the pilot screw. So I put the 50 in and it helped instantly and adjusted the screw and even better. Rode it like that and it seemed to run a little hotter. I adjusted the needle once spot to the 4th position and that helped. I wanted to fine tune the main,but the dealer only had one, the 190. I found out that was way to big, especially when I hit 4th or 5th gear. But through all these adjustments the bike still pulled about the same. It didn't seem any more powerful, it just ran smoother with each adjustment. I was expecting alot with all the raving reviews.

[Which 450?]

u kno whats funny. I have a stock bike besides 450r carb, "open" airbox lid, uni air filter, and a big gun rev box. I have a 180 main, and a 52? pilot. needle in the middle. If I lean anything out it runs like crap. I also have the fuel screw 3 turns out. It runs damn good the way its set up. Plug looks fine also. Did lots of chops when I 1st jetted it.

[zrpilot]

Originally posted by dariusld
When I first got the carb, it came with 175 main and a 48 pilot. I threw it on like that to get a starting point. It idled like caca even when I tried adjusting the pilot screw. So I put the 50 in and it helped instantly and adjusted the screw and even better. Rode it like that and it seemed to run a little hotter. I adjusted the needle once spot to the 4th position and that helped. I wanted to fine tune the main,but the dealer only had one, the 190. I found out that was way to big, especially when I hit 4th or 5th gear. But through all these adjustments the bike still pulled about the same. It didn't seem any more powerful, it just ran smoother with each adjustment. I was expecting alot with all the raving reviews. I had virtually the same mods to my 400EX and used a 175 main.... I doubt you were lean...FWIW.

[RaginRedneck]

ZRPilot,
I have a stupid question for you. How come with the addition of the new carb a stock motor can handle more fuel??? I don't know if my understanding is off, but this is what my question is based off of.

Right now I have a stock carb on my 400 EX. Stock Bore, K&N, closed Air Box, Slip-on, and a CDI Box. My main jet is at 155. If I but the 450R Carb on all of a sudden it sounds like I would be in the 175 main jet area......

I guess i just don't understand why the motor would not be running rich. Just curiosity on my part. Any answer you provide would be appreciated, your knowledge is impressive and I respect your opinion.

Thanks,
-RR-

[Snipe]

Mine did the exact same thing as yours is doing and after changing jets and all other factors several times, open airbox closed airbox change idol adjust throttle settings anything that was attached to the carb I adjusted and or changed and when in 5th gear about half way it would mess up and the engine acted like when you hit the rev limiter but it wasnt the rev limiter it would just spit and sputter and piss me off. I went back to stock and im running stronger than ever. Only thing is I kept the exact same jets from the 450R carb in my stock carb.

[zrpilot]

Originally posted by RaginRedneck
ZRPilot,
I have a stupid question for you. How come with the addition of the new carb a stock motor can handle more fuel??? I don't know if my understanding is off, but this is what my question is based off of.

Right now I have a stock carb on my 400 EX. Stock Bore, K&N, closed Air Box, Slip-on, and a CDI Box. My main jet is at 155. If I but the 450R Carb on all of a sudden it sounds like I would be in the 175 main jet area......

I guess i just don't understand why the motor would not be running rich. Just curiosity on my part. Any answer you provide would be appreciated, your knowledge is impressive and I respect your opinion.

Thanks,
-RR-
The vaccum signature of the 450r carb is COMPLETELY different then the stock carb and therefore you can't compare jetting numbers. Consequently it is this different vaccum characteristics that make the 450R carb work on the 400EX motor providing a crisper throttle repsonse.

[RaginRedneck]

Thanks.

[smokindw]

so if i was running a 190 with the lid on and now i wana take the airbox lid off do i have 2 go fatter or do i need 2 lean her down??

[zrpilot]

More air, more fuel. Fatter.

I find it hard to believe that you were running a 190 with the lid on and think that it is jetted correct :confused:

The 400EX is VERY tolerant of a lean condition for experimentation. It would not hurt the motor to experiment with smaller jets to see if it runs better or worse.... FWIW

[smokindw]

no no that was with the stock carb and a dynojunk kit which was actually a 170dj main which is a 190k. and it actually ran really good. i was just using that as an example so i could find out wether i gota fatter or leaner be4 i start wit my mod 2day cuz im running without the lid now cuz i got a um airbox now. im scrapping the old 450r carb that i put in like 2 weeks ago cuz i dont think i plugged the hotstart off good enough, so i ordered another new carb and this time i ordered the hotstart cable. plus i wanted 2 have an extra 450r carb so i can take it all apart n see exactly how the carb works, well ups just pulled up with the carb YAYYYYYY

[smokindw]

now my ? to u is how do i install the hotstart cable into the carb?? im sure that it basic but i just cant seem to fig it out, is there a thread that u could give me that has pics or directions??
Thanks

[smokindw]

nevermind i fig it out