1150 Kat.. time for engine mods... advise requested!!

[Arronduke]

You're right.
I wasn't aware he had head work done.

No head work has been done.
The motor is standard .... hard to start, it appears that one plug is oiling up real easy at start up. Once started it runs fine. This is with standard carbs.

So here is my experience with RS38's on a standard 1135EFE. Start fine and idles fine. once warm it takes AGES for the idle to settle down. Hangs at like 3,000 RPM. Like I said real hard to change down a gear.

noticed the extra grunt when I opened the throttle and they looked cool.

BUT what do I need to do to the 1150 motor to use them?
I am interested in comments that say they SHOULD work. Even if they are not perfect for a standard engine.

Tell me more.

[Arronduke]

Depending on what you do to the engine in terms of airflow, you should know that original 84/85 1150 black chrome exhaust pipes will mount and align perfectly on your stock Kat frame. To the untrained eye, it'd look stock.

I did not know this.... nice fact to know.
Thanks

[Arronduke]

Here's another comment on the slotted cam sprockets. If you're installing performance cam shafts then they must be degreed in. In my opinion it would be foolish to slap bigger cams in with stock sprockets and therefore no regard for where the timing events are actually occuring at. Also make sure that you have the right valve springs for the cams that you want to use.

The 38RS carburetors will be fine for a 1229cc street bike. Just get a push-pull throttle so the slides don't stick open and you're good to go. I knew a couple guys who had 1229s with 38RS and they were fine street bikes.

One thing I did not see mentioned was a modified clutch basket. With such a hot rod you really need to have the basket welded with an HD kit. The helical gear on the basket causes a side load on the basket which destroys it at some point. Welding the HD kit in makes the chances of that point occuring later rather than sooner more in your favor.

Just re-read this post.
To add, I had a push / pull throttle so I can only assume that the slides were all close and the dam engine's idle would not settle under 3,000 for ages. It would settle to an idle after some time.

dam thing

[gmansyz]

Could be a little lean and out of sync.
G

[isleoman]

Just re-read this post.
To add, I had a push / pull throttle so I can only assume that the slides were all close and the dam engine's idle would not settle under 3,000 for ages. It would settle to an idle after some time.

dam thing

Accelerator Pump? Have you adjusted it?

[jimb12]

Check to see if the push cable is actually pulling the slides closed when you close the throttle as it should. Also make sure there's some free play in the closed position so they aren't being held open slightly.

One more thing, do any of the vacuum nipples covering the sync ports have cracked rubbers?

[rapidray]

Check the cables first. Sync the carbs & then adjust the mixture screws correctly. Set the idle at about 2500 rpm to sync the carbs. Also, are the float heights correct? Ray.

[stetracer]

No head work has been done.
The motor is standard .... hard to start, it appears that one plug is oiling up real easy at start up. Once started it runs fine. This is with standard carbs.

So here is my experience with RS38's on a standard 1135EFE. Start fine and idles fine. once warm it takes AGES for the idle to settle down. Hangs at like 3,000 RPM. Like I said real hard to change down a gear.

noticed the extra grunt when I opened the throttle and they looked cool.

BUT what do I need to do to the 1150 motor to use them?
I am interested in comments that say they SHOULD work. Even if they are not perfect for a standard engine.

Tell me more.

Your problem sounds to me like a broken or cracked slide. some of these RS carbs came with carbon fiber slides that were prone to braking or there way out of sync.
Pop the float bowls off and see what jets are in them.

38RS carbs jetting
Main jet -137.5
pilot jet - 22.5
needle - 9chyo-99 clip on 4th notch from top
needle jet - y-6
fuel screw 1/2 turn out
this jetting should get you very close to perfect



,

[gs scott]

The easy tell on the frame is the brushed aluminum peg mounts on the 83 v.s. the older black ones on the 82. The welded frames mounts are different for the two different pegs mounts. Other differences as you mention but this tells you frame year quiet clearly without looking at serial numbers.

The difference in the VIN is in the middle JS1GU73AxC210xxxx vs D210 (82 is C210, 83 is D210xxxx).
Also, the brake pedal is aluminum in 83, metal in 82.

[Arronduke]

Accelerator Pump? Have you adjusted it?

Checked this and it does not engage until half throttle.
These carbs are quite different to the standard jobs...

[Arronduke]

Check to see if the push cable is actually pulling the slides closed when you close the throttle as it should. Also make sure there's some free play in the closed position so they aren't being held open slightly.

One more thing, do any of the vacuum nipples covering the sync ports have cracked rubbers?

Yep checked the free play and they slides close as they should.

[Arronduke]

Check the cables first. Sync the carbs & then adjust the mixture screws correctly. Set the idle at about 2500 rpm to sync the carbs. Also, are the float heights correct? Ray.

Ray I don't have the float heights or for that matter any info on these things...

Where can I find some info?

[Arronduke]

Your problem sounds to me like a broken or cracked slide. some of these RS carbs came with carbon fiber slides that were prone to braking or there way out of sync.
Pop the float bowls off and see what jets are in them.

38RS carbs jetting
Main jet -137.5
pilot jet - 22.5
needle - 9chyo-99 clip on 4th notch from top
needle jet - y-6
fuel screw 1/2 turn out
this jetting should get you very close to perfect

,

I have had a look at the jets in the carbs.

Main jet 135
Pilot jet 17.5
Fuel screw 1/2 turn
Needle jet looks like 8?
need a magnifying glass.

I obviously need to strip these completely.

[Arronduke]

The offending set of carbs.






and I can only assume that the little jet in the last picture is the needle jet? I have no idea about these carbs..!

Again I need to strip and reassemble to understand how they work. When purchased they were from an old guy who said he had fullly rebuilt them and they were off his 1135EFE.

[Arronduke]

The difference in the VIN is in the middle JS1GU73AxC210xxxx vs D210 (82 is C210, 83 is D210xxxx).
Also, the brake pedal is aluminum in 83, metal in 82.

I hope to have the 1100EZ this week and I will check all the numbers and post
Thanks