Quantcast
Jump to content

  • Do you own an ATV? Join our Forum!

    As a member, you can post in our forums, upload your photos and videos, use and contribute to our downloads, create your own member page, add your ATV events, and even start your own ATV club to host your own club forum and gallery.  Registration is fast and you can even login with social network accounts to sync your profiles and content.

AimlessMoto

1995 Suzuki Quadrunner 250, Idles, bogs 1/4 throttle, fine on top end.

Recommended Posts

Hey guys, new here, but haven't found ANY answer to my specific problem on a Suzuki dedicated ATV forum, so here's to hoping!

I acquired a 95' Quadrunner 250, 4x4, (LT4WD) for practically nothing with no spark. The PO had tossed in a used stator which didn't fix the problem... so I went all routes (though cheaply) to narrow down the initial problem of no spark. 

Plug, coil, CDI (caltric) and stator w/pickup (caltric) were purchased and installed. And it RAN, but bogged horribly and would not rev past 1/4 throttle. 

I checked fuel flow, vacuum lines, all the normal stuff, no issues. I decided to check the valves and cam... well, there was one problem. The cam was 1mm under the lowest spec in the manual. So, in-came a new cam, Stage 1 Hotcams... also threw in a new set of shindy valves, lapped them, replaced the valve seals, and the timing chain. 

Back together again (w/stock airbox and new oiled filter). Now it idles even better, still boggs at 1/4 throttle, but will rev past it if you hold the throttle open for a second. Ahaha... success!

So I was able to ride it above 1/4 throttle once I had momentum... could shift through the gears, all was good as long as I kept it over 1/2 throttle. Took a long enough ride to break in the cam properly at least so I won't have to worry about that. 

Now, I start fiddling with the carb. It's clean as a whistle, stock, with stock jets (new replacement Mikuni jets). Same problem. 

 

I start thinking, maybe this is fuel related and the bike is having an issue transitioning from idle jet to main jet... so I LOWER the needle by raising the clip 1 spot. Now it revvs up in neutral with no bog, but it boggs about the same trying to ride it. So I move the needle down again with the clip on the top slot. Better, but still has a bit of bog at 1/4 throttle. 

The last bit of advice I got was to ditch the CV carb... so I sprung for a brand new Mikuni VM30-83 round-slide. Bolted it up, blew into the vacuum tube to fill it with fuel (no vacuum port on this one) and she fired right up... but there is still a bit of bog, it's just masked by the fact that I'm not waiting for the vacuum diaphragm to open. 

 

So I feel like each little step brings me closer, but not perfect. I'm now wondering if this is still in-fact a carb tuning issue (I have some jets I can fiddle with and maybe lean-out the idle jet a little.) OR if the cheap-a** Caltric Stator/Pickup is what's causing these issues. 

 

I have a 95' KingQuad with 400 miles on it... like new.. runs like a top... I've tried both the stock QR and the Caltric CDI boxes on it, and it revvs up and runs like a champ. 

 

The only unknowns between the two systems are the carb, and the stator/pickup. My next step in troubleshooting is to rip apart the King Quad and test it's CDI on the Quadrunner... but considering there is no change to how it runs I doubt it will lead to a solution. 

 

HOWEVER... I tried the stock CDI just recently after running the Caltric this whole time, and the bike runs like garbage. Hardly idles, and won't rev up at all. So, that is my one smoking gun telling me that it's either the pickup coil or the stator itself. 

 

Has anyone had a problem even CLOSE to this? I can't image the carb would be causing this many issues, especially going to 2 different ones, both with stock jetting to OEM, and exhibiting the identical symptoms... the only change is when different CDI's are plugged in, or when the needle valve leans out the mixture. 

Also, I checked the piston, rings and bore when I had it apart and they're like-new... no scoring, rings are loose, cylinder is still round and has honing marks still int he bore. Stock piston, stock bore size and it has 160psi compression. Battery is brand new, and I've tried 3 different R/R's, none of which change any symptoms, but slightly vary the charging voltage by .2-.5 of a volt depending on which unit. Also tried a new coil which changed nothing. 

ANY help would be appreciated. Too much invested to not get it running right. 

Share this post


Link to post
Share on other sites


Here's a video of it as received and up-to actually riding it. You be the judge! (there is a lot of banter, feel free to skip around). Ride portion is the last 4 mins of the video, 12:22 is how it was before the head rebuild... fluttering and stuttering at 1/4 throttle. 

 

Edited by AimlessMoto
  • Like 1

Share this post


Link to post
Share on other sites

Have you checked the rectifier and voltage coming to the battery ?  I’m curious to see what you have as far as voltage. Rev the engine a bit and see what’s happening.  

 

  • Like 1

Share this post


Link to post
Share on other sites

I just tried all 3. The results are:

Battery was a steady 13.00v prior to test. 

Electrosport: 14.0v idle, 14.4v rev.

Caltric: 13.8v idle, 13.9v rev.

Suzuki (original): 13.9v idle, 13.6v rev. 

The ride and running videos were all with the Electrosport unit installed. 

15611336909781638369830.jpg

Edited by AimlessMoto

Share this post


Link to post
Share on other sites


I just did a no-load test on the AC stator. Set the meter to AC 200V... only getting about 50v per each leg when held at high revs. Me-thinks it may be the issue... which sucks. 3x opening the damn engine, the last time to install this new Caltric stator. So upset. 

 

1561135297753657053136.jpg

Edited by AimlessMoto

Share this post


Link to post
Share on other sites

Well it’s a last ditch effort.  You should test the stator on ohms setting phase to phase and see if the numbers are within range.  

Share this post


Link to post
Share on other sites
32 minutes ago, Frank Angerano said:

Well it’s a last ditch effort.  You should test the stator on ohms setting phase to phase and see if the numbers are within range.  

While running?

Share this post


Link to post
Share on other sites

Engine off and tester on ohms, phase to phase you should get a reading. Somewhere in the 100’s maybe, It’s in the manual. Test each wire to wire and see what you get.  

Do this with the pick up coil also.  

I like to test both ways.  One when the bike is ice cold.   Second is when the engine is hot.  

Most of the time stators go bad and you don’t  have the option of testing while hot because you have no spark.   

The acceptable range will be listed in the manual.  

  • Like 1

Share this post


Link to post
Share on other sites
39 minutes ago, Frank Angerano said:

Engine off and tester on ohms, phase to phase you should get a reading. Somewhere in the 100’s maybe, It’s in the manual. Test each wire to wire and see what you get.  

Do this with the pick up coil also.  

I like to test both ways.  One when the bike is ice cold.   Second is when the engine is hot.  

Most of the time stators go bad and you don’t  have the option of testing while hot because you have no spark.   

The acceptable range will be listed in the manual.  

Sounds good! I did the same test on my r/r and CDI... basic diode resistance test. I'll try that out when I get a minute this weekend and report back! Thanks for the help!

Share this post


Link to post
Share on other sites


I have had similar problems on a couple of machines, one solution was replacing a faulty aftermarket cdi box, another problem for a different machine was a vacuum leak at boot between carb and cylinder head

Share this post


Link to post
Share on other sites
On 6/23/2019 at 6:43 PM, Cj Winds said:

I have had similar problems on a couple of machines, one solution was replacing a faulty aftermarket cdi box, another problem for a different machine was a vacuum leak at boot between carb and cylinder head

I have run 2 different CDI's, and the problem is worse with the stock one... but with a spark tester I have no deviation in spark... it seems to be the mixture. Then again, still unsure if the mixture is just masking the problem. It does run REALLY well once it gets over the hump. 

 

I did complain to Caltric about the low voltage coming out of the stator and they send me a brand new one at no cost. I am tempted to sell it online and put the money towards getting my stock one rebuilt by Ricks Electronics. 

 

I have tossed at VM30 Mikuni on the bike for right now and it SEEMS to be a lot better... (was going to upgrade anyway). I may bite the bullet on another CDI, possibly a used eBay one rather than another Chinese POS. 

Share this post


Link to post
Share on other sites

I’ve never had any luck with aftermarket cheap cdi units.  Always like the oem cdi when it comes down to it.

The Chinese ones look great plug right in but are worthless.  Ive been lucky with caltrec stator coils though.  So far used a few and they’ve been good. 

Thats a great carburetor you put on. Prob cost a bit! $$$ but well worth it.  

 

Share this post


Link to post
Share on other sites

 

Cool video.

 

Does your idle jet have a spring, o-ring and seating washer? ie, all the parts are there?

Share this post


Link to post
Share on other sites
59 minutes ago, Ed Zeppeli said:

 

Cool video.

 

Does your idle jet have a spring, o-ring and seating washer? ie, all the parts are there?

 

1 hour ago, Frank Angerano said:

I’ve never had any luck with aftermarket cheap cdi units.  Always like the oem cdi when it comes down to it.

The Chinese ones look great plug right in but are worthless.  Ive been lucky with caltrec stator coils though.  So far used a few and they’ve been good. 

Thats a great carburetor you put on. Prob cost a bit! $$$ but well worth it.  

 

$70 on Amazon! Genuine mikuni, almost a direct copy of the one on the 87-89 Quadrunner! 

59 minutes ago, Ed Zeppeli said:

 

Cool video.

 

Does your idle jet have a spring, o-ring and seating washer? ie, all the parts are there?

Yup! All new on the CV in the video. Jet was 2.5 turns out. Tried 3, tried 2... both only affected the over-all idle and not the bogg issue. 

Share this post


Link to post
Share on other sites


 

When you describe the issue as being at 1/4 throttle only it kind of rules out spark in my mind and I keep going back to thinking something's up with the carb transitioning from idle circuit to main jet.

  • Like 1

Share this post


Link to post
Share on other sites

the 3 most common things i have seen cause erratic running on these is 1) a plugged fuel tank vent (either improper routing or our friendly mud dauber hornets). 2) is a tiny hole in the fuel pump diaphram (at idle there isn't enough fuel draw, and at WOT there is so much of a pulse it can overcome the leak), and 3) is a delaminating intake manifold. they can delaminate internally as well as externally, so its not always easy to see. the test for the manifold leak is to have the machine idling (engine just warm enough to run without choke), and spray the manifold with water while grabbing the carb moving it in every direction. / its really difficult when you have 2 systems that can be at fault (in this case both electrical and fuel).  the fuel system is easier to diagnose than the electrical, so go there first. i will add that most (but definitely not all) of the electrical problems i saw in the 40 years of doing this was related to a bad ground. a quick way to eliminate that is to run a single wire from a GOOD CLEAN (meaning sanding, filing,etc. all of the paint off) chassis ground, to a CLEAN bolt on the engine case, to the battery - terminal, and then make certain the voltage regulator and CDI box and ignition coil all have CLEAN & TIGHT contacts as well. oh, something else just popped into my head, i have seen a few cases where the ignition coil connector was worked oversize from vibration causing intermittent ignition at specific rpms. tightening the contacts up by either replacing or bending them to increase the tension fixes that. its a lot of things, but i hope it helps.

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Similar Topics

    • By Ryan Foster
      I am trying to find a used OEM cylinder for the above mentioned quad. I was told the current cylinder came from Amazon so I suspect its aftermarket china (made from recycled coat hangers and shopping carts.) Anyway, was looking at the parts list and they have 2 cylinders listed..
      11210-19B82-0F0
      MODEL X/Y
      and..
      11210-19B90-0F0
      MODEL K1/K2

      My engine case is stamped K403 230829 Trying to figure out what model I have. I see I have a K in there but....
      I don't know what the differences are between the cylinders (the first one cost more). Anybody know how to decipher this?
      I only have the engine, I don't have the frame to get the actual VIN.  

      Also, are there any marks on an OEM cylinder to differentiate it from aftermarket?
       
    • By Frank Angerano
      So i took a road trip today to look at a Suzuki Eiger! 2006 in perfect condition other then the fact it starts for 30 seconds and shuts down.  
      Its been sitting for about a year in a shed. 
      It has a plow and a winch included!!!
      Got it for a really good price and all looks good so far.  
       
      Stay tuned.  





    • By Mike Hooper
      Hi everyone! I'm from New Zealand, and doing up a Suzuki Lt50 for the kids. This is the first bike I've ever worked on, and it's currently not running. Hoping that both Google and this forum will get me through! Haha

    • By Amazon Ads
      Where do you buy your ATV parts? Did you know that Amazon has ATV parts in stock for immediate delivery? You'll find all the best ATV parts and for great prices! Check out all the ATV parts available with free 2 day shipping now...
    • By Julio Cano
      The tires which I bought on ebay cannot be balanced, it’s out of round.Tried riding and had wobble. 
      It was mounted in shop and they also put it on a rim they had sitting in the shop and same issue to confirm it.
      Are they defective ?
      They have brand new high quality tires for my  old suzuki gsxr750 and want about $600 for two tires.
      Is it worth it to pay that much or buy another set of front rear tires like Hexautoparts which has good reviews on trustpilot.com?
      Any recommendations ?
      Thank you.
  • Similar Tagged Content

    • By Aaron Drost
      Hello bought my 2000 polaris sportsman 500 last week bike seems to work pretty good untill yesterday, when in reverse the bike seems to start bogging out? How come? 
    • By Quadrunner44
      I have an older 1980s Suzuki quadrunner red lt 4wd (250)
      so just finished putting it all back together and was running fine just needed to adjust the rebuilt carb
      bf decides to hook up an air chuck to the gas tank because it got a shot of air in the gas line well 120psi didn’t agree with any of the parts including the new carb 
      end result : new battery new carb now it just clicks (one single click) won’t turn over 
      hard to pull start gets hung up (unless I remove the spark plug ) gas flooded out the first time but now does nothing purchases a new starter waiting the arrival 
      could there be damage to the crank shaft or pistons etc? Or install the new starter and try to fire it up ? What caused the starter to die after he flooded everything with gas was working fine. 
      Thank you 
    • By Kevin Nicoll
      Anyone familiar with these models? Its a new to me quad, picked it up for basically nothing... Just time and materials now, this looks expensive. 




    • By jim estes
      Aquired a Quadrunner 240 about a year and half ago.The man said he knew nothing of it history just took it a s an add on in a trade he had made, It looked good-early/mid 90's all the plastic in good shape with no obvious oil stains, dents, etc, now have time to check it a little cl;oser...any suggestions as to what to look for? Aside from metal shavings, checking fluids etc? Whats good to see? Bad? Thank ahead
       
    • By Admin
      View File 1985-90 Suzuki Quadrunner LT230 Service Manual
      1985-90 Suzuki Quadrunner LT230GE, LT-F230G, LT230S Service Manual
      Submitter Admin Submitted 06/29/2019 Category Suzuki ATV  
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...