R1 Carbs (lots of pics)

[HudsonMC]

Ok ok ok.....before you all go crazy I'm ordering my wideband on the next paycheck!!

 

But for now, i picked up #22.5 jets from cycle barn. This is a video of it at idle, full warm(after a test drive) with the screws 2 turns out.

 

I'm getting some results, but I dont think for the right reasons. It takes even longer on decel for the popping to start. like 10 seconds. Even longer with 3 turns out. But now I'm gettting smoke. With 3 turns out ALOT of smoke, to the point where I freaked for a second thinking I toasted my rings or something. I DID just do the first oil change since I built the motor so could that have something to do with it???? I don't know but the smoke was reduced by going back to 2 turns out so....

 

 

Anyway, here is the pop at idle. Nothing ive done seems to fix this. O well. Waiting for wideband now. Starting to think its something else besides jetting............who knows.........

 

Enjoy.

 

http://youtu.be/_WWz22-Rl_k

 

Isn't that booming in-the-exhaust afterfire indicative of an over-rich condition? Unburned fuel igniting in the exhaust...Has it always been like that, or did you ever get any pops or backfire from the intake? Try going back to the 17.5's 2-2.5 turns out and see what happens?

 

I've just about stripped one of the fricking clamp screws from taking these things on and off my car so much.

[Farmer Joe]

vintage, this really sounds like an over rich condition, and a vacuum leak.. but that shouldnt make it pop that profoundly..

 

have you done a leak-down test to make sure you dont have a bent valve or something?

 

dude, ive had piggy carbs on my vehicles in the past, and none have ever popped like that at idle.. decel was always just just a sound of the unlit fuel in the exhaust lighting, and making a deep pop.. its a different sound that just a regular decel burble, if that makes any sense.

 

are you sure that intake is air tight?

 

edit: i listened to the video again...

 

have you from the get go had this pop? im wonderin if you burnt and exhaust valve or 2 with it open header? hope not, but thats kinda what it sounds like..

[Rays74]

Verify that the carbs are sync'd before doing any mixture adjustments, it's part of your tuning ritual now that you have ITB's. Listen to it idle, behind the pops you can hear "blub-blub-blub" instead of smooth........that's what I'm on about.

Been there, heard this B)

 

Here's an older KZ650 sound file that gives an idea what a well synchronized set of carbs sound like.....

[VintageRice]

Well, you guys have given me alot to look at. I hope it isn't the valves. It's a freshly rebuilt head.

I've checked for vacuume leaks with the old aresol spray test. But I should make a leak down tester and test each intake runner under pressure. Just to make sure I'm sealed up on all four cyls. I never ran it open header.

[VintageRice]

As far as the over rich condition on idle, it probably is now. But before when I had the stock 15 jets in there(stock for the bike) it popped more. In fact Turing it down to two turns out on #15's the popping was rediculous. Overall Richening it helped reduce popping on decel and idle. But didn't cure it and now I'm overly rich. I just gotta get it synced, do a leak down test and tune with wideband. I do have a small exhaust leak at the downtube past the end of the header. Gotta get that fixed too

[HudsonMC]

As far as the over rich condition on idle, it probably is now. But before when I had the stock 15 jets in there(stock for the bike) it popped more. In fact Turing it down to two turns out on #15's the popping was rediculous. Overall Richening it helped reduce popping on decel and idle. But didn't cure it and now I'm overly rich. I just gotta get it synced, do a leak down test and tune with wideband. I do have a small exhaust leak at the downtube past the end of the header. Gotta get that fixed too

 

Oh yeah, fix that exhaust leak for sure. That could be it right there. That's encouraging. With your welding skills, should be a quick job.

[Farmer Joe]

yeah, id really get on doing a cylinder leak down..

 

theres nothing else i can think of that would cause that pop.

[DADZSUN]

Ray, interesting that you've got two runners tapped, is that for a smoother vacuum?

 

 

My Bogg manifold has a single on #1 and the vacuum is sufficient to advance the timing.

[DADZSUN]

Vintage, grab the STE - SK flow meter: http://www.cbperformance.com/catalog.asp?ProductID=572

 

I've got one and it's was super easy to sync.

[Rays74]

Ray, interesting that you've got two runners tapped, is that for a smoother vacuum?

 

 

My Bogg manifold has a single on #1 and the vacuum is sufficient to advance the timing.

 

Nope, not my manifold. Just a pic to explain if they were true ITB's, not linked by a vacuum tube.

 

Interesting meter, Dadzsun........kinda like a VW unit we used for the dual Solex's backintheday :)

[Drummerboy4as]

It's my manifold. The larger nipple on the rear runner is for the brake booster the front is for the vaccum advance.

I plan to tap the middle two also to give me better vaccum for my auto tranny. Been having issues with hard shifting due to weak vaccum.

[72240z]

My mikumi was set up for a front advance and rear brake booster but fabed up this vac manifold because lots of people claim to have problems with weak vac otherwise.

[Farmer Joe]

see!! ^^^^

 

thats what al these r1 intakes need to have...

 

they dont need a balance tube, but at least each runner tapped to pull vacuum from..

 

brilliant intake there, 72240z.

[slingshot532]

Rice,

 

I think you have an intake leak of some sort. Mine made the exact same poping when the carb coupler came loose on one runner. I think I could replicate it by loosening the bands holding one carb. It happened twice, the second time I knew right away because of the pops, plus it started running lean. When you get the A/F gauge that will tell you fo sho.

 

Good luck, sounds good otherwise.

 

:thumbup:

[72240z]

Thanks farmer joe.

someone did a really nice job on bike tbs though not these

Very nice way of doing it in my opinion, sexy set up

[VintageRice]

^^^^^^SCHWING^^^^^^

[VintageRice]

Still, all that work on that intake setup above and they chose to use screw style clamps. They cut into rubber, look cheap, and hold poorly. Why dont more people use T-bolt clamps like mee!! :D

 

They are so much better.

 

[72240z]

Ya its true, those clamps are for shit. T bolts even on looks alone kick ass.

[spudly13]

Ya its true, those clamps are for shit. T bolts even on looks alone kick ass.

 

im gunna have to disagree with you guys here... T bolts while they work good, are big, bulky, break often, and suck to tighten/loosen, on something like holding the carb couplers i like the hose clamps better as long as there new they will tighten plenty and are way less bulky then the t bolts ( not to say t bolts dont have there place, like intercooler couplers)

 

VIntage it sucks your having all these problems with the carbs, i guess i was lucky with mine, a little tuning and bam rocked em til the motor blew, even with boost lol

[VintageRice]

Ya. Probly my own fault. Leak somewhere or not having the propper tuning tools. All in all though the car runs good and rips! Just that idle issue.

[slingshot532]

I drove around all day Saturday looking for filters that would fit on the carbs, but I couldn't find a full set anywhere. So I faked up some intake screens with screen door screen and zip ties and drove out to the mountains today. I tried using cut up rags but they had too much resistance and the engine would bogg at about 3000 rpm. I don't know the PPM count on these "filters", but at least it kept the bigger rocks out. I drove from San Diego to Pine Valley (about 45 min) and back with no problems. I wanted to see how altitude affected the tune. I got to about 4000 ft with no noticable change.

 

 

Rice, any progress?

[VintageRice]

Not really. Been really busy. Drove the car this weekend a little but broke down due to my fuel tank full of crap again. I rally gotta pull that tank and clean it properly or get a fuel cell.

 

My carbs are hanging rpms a little if I let of gradualy. Then if i blip the throttle it comes right down. I think maybe my couplers are pushing on the linkage and causing it to hang a little.

 

I'm not sure if all four carbs are rigidly attached with the linkage or if one can hang while the rest close. But if it can that would DEFINATLEY throw it out of sync for a second. Will get into it soon as I get a spare minute.

 

I did get a start on building my intake runner leak down tester out of PVC. How much pressure should I put in each runner and for how long to measure leak down ?? I guess really nothing should leak out of the intake runners right? yeah. That makes sense.

[HudsonMC]

Not really. Been really busy. Drove the car this weekend a little but broke down due to my fuel tank full of crap again. I rally gotta pull that tank and clean it properly or get a fuel cell.

 

My carbs are hanging rpms a little if I let of gradualy. Then if i blip the throttle it comes right down. I think maybe my couplers are pushing on the linkage and causing it to hang a little.

 

I'm not sure if all four carbs are rigidly attached with the linkage or if one can hang while the rest close. But if it can that would DEFINATLEY throw it out of sync for a second. Will get into it soon as I get a spare minute.

 

I did get a start on building my intake runner leak down tester out of PVC. How much pressure should I put in each runner and for how long to measure leak down ?? I guess really nothing should leak out of the intake runners right? yeah. That makes sense.

 

I don't think there is a bar that goes through all the carbs. There's little springs that actuate the next carb in line. I don't think there is a way the could bind. It might be worth cleaning all the grime out and spraying some grease in there though.

 

The RPMs sticking like that is a symptom of the carbs being out of sync though. Sync 1vs2, 3vs4, then 2vs3.

[spudly13]

One could hang open if one of the two bolts running through all 4 carbs is to tight, however that would be noticeable with the car just sittimg so I doubt its your problem

[DADZSUN]

Hanging RPM - I've had the same thing on my L16 and posted several pages ago about it. Although, for the last couple of months it no longer seem to be an issue. I actually attributed it to my L16 because I had similar issues with the OEM Hitachi carbs. My R1 carbs were synched when the problem appeared.

 

Vintage: My 510 recently starting showing rust in the gas again after almost a full year of no issues and almost daily operation. Weird. I took an afternoon and pulled the tank and did the 'ol gravel routine. I repeated this cycle (shake gravel in the tank and rinse until the water coming out is clear - let it dry well!) several times and now it runs clear.

 

Update on my KA24e/R1 install (this winter): engine is being rebuilt (.020 over). PO somehow got a screw jammed in the head and valve so a refurbed head with 3-angle and JWT cam are now in my possession. I will be drilling out the provision for L16 mechanical pump soon. Hacked up OEM intake manifold (cheaper shipping to UK) was sent to Bogg a couple of weeks ago as a template for a new one. I discovered that I can run the 240sx flywheel/clutch on my D21 KA24e so long as I run a 240sx starter as well. There are WAY more cheaper lightweigh flywheel (225mm) options for the 240sx than on the truck (240mm). I will be trying to make the rear sump D21 oil pan work instead of flipping the cross member.