Need jet suggestions for carb re-work.
Road Captain
Joined: Oct 2007
Posts: 634
Likes: 8
From: Plum & Nearly
RE: Need jet suggestions for carb re-work.
ORIGINAL: Jumpman
I am a happy fella.
I'm sure there will be a bit of tweaking that I need to do - but the bike runs a TON better than it did since I put the new breather on.
I went to the local sho around lunchtime and grabbed a #45 slow jet. Came back to the house (I work from home a couple of days a week) and installed it. Whole process took about 25-minutes - It woulda been done in 15 if the stock jet woud have played nice - I ended-up having to bend a screwdriver so i had enough leverage to break the jet loose. It DID NOT wanna come out.
SO.. screwed the new jet in place - and ran the bike up the street for a quick test (less than am mile total) and I am now smiling as I am printing my reports.
It's the little things that really can change your day.
I am a happy fella.
I'm sure there will be a bit of tweaking that I need to do - but the bike runs a TON better than it did since I put the new breather on.
I went to the local sho around lunchtime and grabbed a #45 slow jet. Came back to the house (I work from home a couple of days a week) and installed it. Whole process took about 25-minutes - It woulda been done in 15 if the stock jet woud have played nice - I ended-up having to bend a screwdriver so i had enough leverage to break the jet loose. It DID NOT wanna come out.
SO.. screwed the new jet in place - and ran the bike up the street for a quick test (less than am mile total) and I am now smiling as I am printing my reports.
It's the little things that really can change your day.
buy the dynojet kit.....change the spring, drill the slide, punch the air/fuel slow speed plug and adjust according to instructions,change the needle as per thier instructions, change the pick up tube and install the 195 main jet along with a 48 pilot jet (pilot jet is not included withe the kit). This kit is complete with all parts (except pilot jet) and includes drill bits for drilling where indicated.
Thread Starter
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Road Warrior
Joined: Dec 2006
Posts: 1,573
Likes: 138
From: StL, MO. USA
RE: Need jet suggestions for carb re-work.
ORIGINAL: twincam47
Dont know how that could happen....My books indicate that a 45 pilot jet is stock and 190 is the main jet.......you need a 48 pilot and a 195 main.
buy the dynojet kit.....change the spring, drill the slide, punch the air/fuel slow speed plug and adjust according to instructions,change the needle as per thier instructions, change the pick up tube and install the 195 main jet along with a 48 pilot jet (pilot jet is not included withe the kit). This kit is complete with all parts (except pilot jet) and includes drill bits for drilling where indicated.
ORIGINAL: Jumpman
I am a happy fella.
I'm sure there will be a bit of tweaking that I need to do - but the bike runs a TON better than it did since I put the new breather on.
I went to the local sho around lunchtime and grabbed a #45 slow jet. Came back to the house (I work from home a couple of days a week) and installed it. Whole process took about 25-minutes - It woulda been done in 15 if the stock jet woud have played nice - I ended-up having to bend a screwdriver so i had enough leverage to break the jet loose. It DID NOT wanna come out.
SO.. screwed the new jet in place - and ran the bike up the street for a quick test (less than am mile total) and I am now smiling as I am printing my reports.
It's the little things that really can change your day.
I am a happy fella.
I'm sure there will be a bit of tweaking that I need to do - but the bike runs a TON better than it did since I put the new breather on.
I went to the local sho around lunchtime and grabbed a #45 slow jet. Came back to the house (I work from home a couple of days a week) and installed it. Whole process took about 25-minutes - It woulda been done in 15 if the stock jet woud have played nice - I ended-up having to bend a screwdriver so i had enough leverage to break the jet loose. It DID NOT wanna come out.
SO.. screwed the new jet in place - and ran the bike up the street for a quick test (less than am mile total) and I am now smiling as I am printing my reports.
It's the little things that really can change your day.
buy the dynojet kit.....change the spring, drill the slide, punch the air/fuel slow speed plug and adjust according to instructions,change the needle as per thier instructions, change the pick up tube and install the 195 main jet along with a 48 pilot jet (pilot jet is not included withe the kit). This kit is complete with all parts (except pilot jet) and includes drill bits for drilling where indicated.
The indy said they normally don't have to change the main jet when they do breather/exhaust. One of the sites I did research on said the same thing.We'll see how it rides on the Hwy & I'll makeany necessary changes later.
I am just glad to have something that is (very) ridable. The rest will just be some fine-tuning.
Road Warrior
Joined: Jul 2006
Posts: 1,532
Likes: 7
From: Rochester N.Y.
RE: Need jet suggestions for carb re-work.
If you're just getting started with jetting the bike , knowing the baseline is helpful.
The first thing to do is make sure the mixture screw is uncovered , once it is you can adjust it slightly.
Usually you will need a bit more than it will give you this way.
If you do in fact have a #42 pilot jet , then going to a #44 (stock sportster)or #45 (stock newer TC) would probably work for you.
Mine was stock at #45 so I went to a #46 for a while then to a #48 which worked well for "my bike".
I picked up a couple jets locally and one from JP Cycles catalog.
Once you have the idle where you want it to be , shimming the jet needle helps a bit for more rpms in the power curve.
I played with 1 shim then 2 and it got better each time.
I finally went with a 27094-88 (sportster needle) longer taper/slightly smaller diameter , and was better still.
Ran better and the fuel mileage went up slightly.
The main jet (mine was a #190) is fine , I went up to a #195 and the fuel mileage dropped of slightly , so it's a bit too much actually.
The EPA isn't real concerned with full throttle , so the stock main is fairly close as is.
Just pay attention to how it runs and read the plugs , do one thing at a time so you know it's repeatable , and you'll get it right.
The stock CV carb is pretty easy to work with , and takes to jetting changes very well.
I only use stock spark plugs , if you don't , just make sure you keep the same ones all the time , as you will get another variable in your tuning.
Good luck
Mick
The first thing to do is make sure the mixture screw is uncovered , once it is you can adjust it slightly.
Usually you will need a bit more than it will give you this way.
If you do in fact have a #42 pilot jet , then going to a #44 (stock sportster)or #45 (stock newer TC) would probably work for you.
Mine was stock at #45 so I went to a #46 for a while then to a #48 which worked well for "my bike".
I picked up a couple jets locally and one from JP Cycles catalog.
Once you have the idle where you want it to be , shimming the jet needle helps a bit for more rpms in the power curve.
I played with 1 shim then 2 and it got better each time.
I finally went with a 27094-88 (sportster needle) longer taper/slightly smaller diameter , and was better still.
Ran better and the fuel mileage went up slightly.
The main jet (mine was a #190) is fine , I went up to a #195 and the fuel mileage dropped of slightly , so it's a bit too much actually.
The EPA isn't real concerned with full throttle , so the stock main is fairly close as is.
Just pay attention to how it runs and read the plugs , do one thing at a time so you know it's repeatable , and you'll get it right.
The stock CV carb is pretty easy to work with , and takes to jetting changes very well.
I only use stock spark plugs , if you don't , just make sure you keep the same ones all the time , as you will get another variable in your tuning.
Good luck
Mick
Thread Starter
|
Road Warrior
Joined: Dec 2006
Posts: 1,573
Likes: 138
From: StL, MO. USA
RE: Need jet suggestions for carb re-work.
ORIGINAL: Mick
If you're just getting started with jetting the bike , knowing the baseline is helpful.
The first thing to do is make sure the mixture screw is uncovered , once it is you can adjust it slightly.
Usually you will need a bit more than it will give you this way.
If you do in fact have a #42 pilot jet , then going to a #44 (stock sportster)or #45 (stock newer TC) would probably work for you.
Mine was stock at #45 so I went to a #46 for a while then to a #48 which worked well for "my bike".
I picked up a couple jets locally and one from JP Cycles catalog.
Once you have the idle where you want it to be , shimming the jet needle helps a bit for more rpms in the power curve.
I played with 1 shim then 2 and it got better each time.
I finally went with a 27094-88 (sportster needle) longer taper/slightly smaller diameter , and was better still.
Ran better and the fuel mileage went up slightly.
The main jet (mine was a #190) is fine , I went up to a #195 and the fuel mileage dropped of slightly , so it's a bit too much actually.
The EPA isn't real concerned with full throttle , so the stock main is fairly close as is.
Just pay attention to how it runs and read the plugs , do one thing at a time so you know it's repeatable , and you'll get it right.
The stock CV carb is pretty easy to work with , and takes to jetting changes very well.
I only use stock spark plugs , if you don't , just make sure you keep the same ones all the time , as you will get another variable in your tuning.
Good luck
Mick
If you're just getting started with jetting the bike , knowing the baseline is helpful.
The first thing to do is make sure the mixture screw is uncovered , once it is you can adjust it slightly.
Usually you will need a bit more than it will give you this way.
If you do in fact have a #42 pilot jet , then going to a #44 (stock sportster)or #45 (stock newer TC) would probably work for you.
Mine was stock at #45 so I went to a #46 for a while then to a #48 which worked well for "my bike".
I picked up a couple jets locally and one from JP Cycles catalog.
Once you have the idle where you want it to be , shimming the jet needle helps a bit for more rpms in the power curve.
I played with 1 shim then 2 and it got better each time.
I finally went with a 27094-88 (sportster needle) longer taper/slightly smaller diameter , and was better still.
Ran better and the fuel mileage went up slightly.
The main jet (mine was a #190) is fine , I went up to a #195 and the fuel mileage dropped of slightly , so it's a bit too much actually.
The EPA isn't real concerned with full throttle , so the stock main is fairly close as is.
Just pay attention to how it runs and read the plugs , do one thing at a time so you know it's repeatable , and you'll get it right.
The stock CV carb is pretty easy to work with , and takes to jetting changes very well.
I only use stock spark plugs , if you don't , just make sure you keep the same ones all the time , as you will get another variable in your tuning.
Good luck
Mick
I still have not had a chance to get out and 'really' ride the bike to see how the changes impact mid-range & top-end power. I've kinda been locked into subdivision for my test rides - as I don't wanna leave my daughter home alone too long.
IFrom what I have seen so for - I think the move to a #45 slow jet (from a #42) solved 90% of the problems I was having. I did a little more research last night, and I think that adding a washer or two will get me to where I want to be. I should have a good balance of performance (slightly better than stock) and still get good fuel economy.
I have not yet removed the plug for the idle/air screw - as all the work I have done so far has been with the carb still on the bike. So - we'll see how it all works-out once I do that. I also want to get a new set of plugs to before I start messing with it anymore. I shoulda pickedthem up yesterday - but it slipped my mind.
Road Warrior
Joined: Jul 2006
Posts: 1,532
Likes: 7
From: Rochester N.Y.
RE: Need jet suggestions for carb re-work.
The next thing to do is get the idle mixture screw out and fine tune the idle.
I managed to drill the cap (real carefully) without removing anything on the bike.
Make a note of how many turns in till the stop you have , and be gentle.
Just set it for the best idle at 1000 rpms (or whatever yours calls for).
You should stop there and run a few tanks through and do a fuel mileage average.
Read the plugs and see if they're a bit lean (white).
The #45 pilot will take care of your idle and just off idle circuit.
The exhaust note should be more stable and and the engine slightly cooler in traffic.
After a few tanks , see if the throttle response is just a pinch lazy higher up the throttle range.
I ran about 50 mph in 5th and turned the throttle maybe 1/16" "more" and it did nothing.
Then turned it about 1/16" "more" and nothing , the next 1/16" did something , so the power was slightly flat (lean) in that range.
That's when I added 1 #4 machine shim under the jet needle.
Tested again and got better response at the second 1/16".
Then added 1 more #4 machine shim and got response at the first 1/16" of throttle movement.
This may do it for you and I could have stopped there.
The sportster needle did just a pinch (and I mean Pinch)better so I stopped there and am happy.
Great mileage and performance for about $20.00 and some time , a pretty good deal nowadays.
Good luck
Mick
I managed to drill the cap (real carefully) without removing anything on the bike.
Make a note of how many turns in till the stop you have , and be gentle.
Just set it for the best idle at 1000 rpms (or whatever yours calls for).
You should stop there and run a few tanks through and do a fuel mileage average.
Read the plugs and see if they're a bit lean (white).
The #45 pilot will take care of your idle and just off idle circuit.
The exhaust note should be more stable and and the engine slightly cooler in traffic.
After a few tanks , see if the throttle response is just a pinch lazy higher up the throttle range.
I ran about 50 mph in 5th and turned the throttle maybe 1/16" "more" and it did nothing.
Then turned it about 1/16" "more" and nothing , the next 1/16" did something , so the power was slightly flat (lean) in that range.
That's when I added 1 #4 machine shim under the jet needle.
Tested again and got better response at the second 1/16".
Then added 1 more #4 machine shim and got response at the first 1/16" of throttle movement.
This may do it for you and I could have stopped there.
The sportster needle did just a pinch (and I mean Pinch)better so I stopped there and am happy.
Great mileage and performance for about $20.00 and some time , a pretty good deal nowadays.
Good luck
Mick
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