Iv'e got a '94 WB. My problem is that it has a bog at low revs. After it spools up it goes like hell. Go down the lake at wot then slow for the turn and when you get back in it its just a little lazy getin goin. The mods are Riva pipe pro tek head and porting and dual carbs. I pulled the carbs just to make sure they were not gummed up(ski was sitting for a while) and everything looks ok.But I did notice while pulling them that the pulse lines were hard as rock. If they were leaking could that cause the bog? Thanks:dunno:
Tuning Help
- Thread starter tall1
- Start date
- Location
- Winnipeg Manitoba
If the pulse lines were leaking it would probably blow up, but it wouldn't hurt to change them if they are hard like a rock.
Did you check your compression? It would be a good idea to rebuild the carbs if it has been sitting for a while.
Did you check your compression? It would be a good idea to rebuild the carbs if it has been sitting for a while.
oldskoo
local jackass
- Location
- Cleveland Ohio
....
sounds like a pop off psi issue,been fighting the same prob with a buddys ski, what's your jetting specs>??
sounds like a pop off psi issue,been fighting the same prob with a buddys ski, what's your jetting specs>??
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
145 psi with an aftermarket head is pretty low compression.
it might could be improved SOME with better tuning, but my assumption is you really need a top end rebuild.
EDIT- I guess it could be the porting causing the low compression numbers.
has it ever ran well for you?
is it a new boat to you?
it might could be improved SOME with better tuning, but my assumption is you really need a top end rebuild.
EDIT- I guess it could be the porting causing the low compression numbers.
has it ever ran well for you?
is it a new boat to you?
- Location
- Near Seattle WA
Tuning tips for Rookies.
This might help?
Tuning tips for Rookies.
*** YOU must use the tachometer to tune *** Do not trust the peak RPM reading; you must watch the tach while riding.
Start with the screws set at 1 turn out, and tune with the tachometer for peak Rpm, then stop there and count the number of turns on the high speed screws. Write this down on a piece of paper.. Then turn the high speed screws in all the way and open them to 1/4 turn open. (Now you will be testing starts only, so no more big high rpm trips around the course). You are only turning in the high speeds to allow you to easily tune the low speeds.
Now check the low speed screws and set them at 1 turn and do a practice start; To test the low speed setting pretend that you just jumped the start and you have to start with no holder. Hold the ski by yourself and hold as many Rpm as you can (don't blow it out first for testing) and then nail the throttle hard.... NO FARTHER THAN 50 KILOMETERS, as you are only testing the start response
If it blubbers like a schoolgirl trying to guzzle a quart of beer, then it's too rich on the low speed screws..
If it falls flat on the line (like someone punched you in the stomach).. It's too lean on the low speed screws.
When you like the acceleration off the line, stop there and count the number of turns on the low speed screws. Write this down on a piece of paper.. Then re-set your high speed screw where they show the best peak Rpm earlier and try both a start and a peak Rpm run...
It will probably "blubber" a little off the line... DO NOT turn in the low speed screws... Instead, go back out on the course and fine tune for peak Rpm again.. The blubbering off the line is caused by having too much fuel in the high speed circuit... Write down your new high speed setting on the piece of paper along with the best low speed setting that you found earlier, this will be your base-line carburetor settings.
If the high or low speed screws are open more than 11/4 turns, then you need to swap to the next bigger jet.
If the high or low speed screws are closed all the way, then you need to change to the next size smaller jet.
*** If no matter what you try, it still won’t leave the line without falling on its face "lean bog"... Then try the next size lower pop-off spring in the carbs... Don't be afraid to try #95 or even #80 gram springs..
This might help?
Tuning tips for Rookies.
*** YOU must use the tachometer to tune *** Do not trust the peak RPM reading; you must watch the tach while riding.
Start with the screws set at 1 turn out, and tune with the tachometer for peak Rpm, then stop there and count the number of turns on the high speed screws. Write this down on a piece of paper.. Then turn the high speed screws in all the way and open them to 1/4 turn open. (Now you will be testing starts only, so no more big high rpm trips around the course). You are only turning in the high speeds to allow you to easily tune the low speeds.
Now check the low speed screws and set them at 1 turn and do a practice start; To test the low speed setting pretend that you just jumped the start and you have to start with no holder. Hold the ski by yourself and hold as many Rpm as you can (don't blow it out first for testing) and then nail the throttle hard.... NO FARTHER THAN 50 KILOMETERS, as you are only testing the start response
If it blubbers like a schoolgirl trying to guzzle a quart of beer, then it's too rich on the low speed screws..
If it falls flat on the line (like someone punched you in the stomach).. It's too lean on the low speed screws.
When you like the acceleration off the line, stop there and count the number of turns on the low speed screws. Write this down on a piece of paper.. Then re-set your high speed screw where they show the best peak Rpm earlier and try both a start and a peak Rpm run...
It will probably "blubber" a little off the line... DO NOT turn in the low speed screws... Instead, go back out on the course and fine tune for peak Rpm again.. The blubbering off the line is caused by having too much fuel in the high speed circuit... Write down your new high speed setting on the piece of paper along with the best low speed setting that you found earlier, this will be your base-line carburetor settings.
If the high or low speed screws are open more than 11/4 turns, then you need to swap to the next bigger jet.
If the high or low speed screws are closed all the way, then you need to change to the next size smaller jet.
*** If no matter what you try, it still won’t leave the line without falling on its face "lean bog"... Then try the next size lower pop-off spring in the carbs... Don't be afraid to try #95 or even #80 gram springs..
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Randy, that is by far the best discription on how to set up the carbs I have read yet. Gonna add that to the Tech Faq section. I suck at tuning, but doing it that way, seems like a no brainer.......... Thank You.
DAG
Yes, my balls tickled from that landing
- Location
- Charlotte, NC
randy, or anyone for that matter. what tach/s do you recommend using, so you can read it and ride at the same time? and experience with a lazier tachometer?
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Philip Clemmons
Owner, P&P Performance
- Location
- Richmond, Va
The PET 2100 or similar seems to be the best. They have rapid sample rates, and are high quality.
A tiny tach samples too slow for accurate carb tuning.
A tiny tach samples too slow for accurate carb tuning.
DAG
Yes, my balls tickled from that landing
- Location
- Charlotte, NC
I'v been thinking long and hard about this and cant figure it out.... would someone enplane why once you preliminary set the high end, (why not leave it "tuned") why lean it out b4 tuning the low adjusters?
Philip Clemmons
Owner, P&P Performance
- Location
- Richmond, Va
The fuel circuits overlap quite a bit. Excess fuel in the high circuit (which is functioning as early as 30-40% throttle) could mask a low speed lean condition. This way you are dialing in the low speed only. Then you retune and readjust the high. Fuel added in the low end carries all the way through, hence the need to possibly retune and lean out the high speed.
All this ASSUMES the pilot, main, and pop-off are correct.
I must say I have never done it this way, but it makes sense...............
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Philip Clemmons
Owner, P&P Performance
- Location
- Richmond, Va
Not likely on the orings, but possible. Typically they would blow and you would have VERY low compression.
Also, the Protec heads dont always run a ton of compression. A 701 blaster I recently worked on had 160-170 ish with no porting and a Protec head, so you may not be far off.
Do you know the cc of the head?
Ericfox
Do it twice?That's DooDoo
- Location
- Akron area --> OHIO!
Tall1... where are you at in NE Ohio? If you live near me I can help out this weekend if you wanna bring it to the lake... let me know...
No I dont know what cc the heads are. All I can tell you is that it is a cast Protec girdled head.
I live in Bristolville it's about 15 min North of Warren. I appreciate the offer but I bought this Blaster w/out a title so I can't take it to the lake (no registration). I have a lake at my house so it was not a big deal that it didn't have one when I bought it. I'm going to try and tune the carbs this weakend and see what happens. If that dosen't work Ill look into doing the topend. Do the 701's have Nicasil cyliders? It would be nice if I could just throw a set of pistons and rings in it.
I put hevier springs in when I rebuilt the carbs just to see if it made a differance. But it ran just the same, and I don't know what jets are in it. Should have wrote it down but I didn't thinks it was in issue at the time. Where at in Clev. are you? I'm about 45 min SE of downtown.