Question about Aprilia RX 125 Motorcycles

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Cpi sm 50 engine has been rebuilt. i have fitted new auto choke,new battery. carb has been stripped and cleaned, slightly bent the float to allow more petrol in thinking the bike might be starved of petrol,still the original low level exhaust on it. it starts well and ticks over well ,the throttle needle is at its highest position, the bike has a power band when riden but splutters and has no power. the previous owner said it would do 60mph

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Sounds like it is running too rich i would set the float height to the recommended height and put a new spark plug in it,is it using a standard air filter ?

Posted on Oct 18, 2015

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  • Aprilia Master
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Hi Gusowz, put the throttle needle and float height back to their original position, I am sorry you can't find the first and best tool you ever bought for your Aprilia but despair not for a mere $10 you can download another one. For more information about your issue, please visit the websites below. Good luck and have a nice day.

Posted on Oct 18, 2015


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
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Posted on Jan 02, 2017

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SOURCE: XR 100 didnt move for a year.My bad so i cleaned

First Make sure you have all new fresh gas,and new fuel filter,Then check the intake tube between the head and carb for cracks or leaks,And You'll need to go back through the carb again as this is a carb issue,But without doing the above first,a clean carb won't be clean for long.

Posted on May 17, 2009

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SOURCE: Suzuki GSF400 Bandit problems with tick over.

as you have replaced carbs you will need to retune for fuel intake also check its getting enough air ie.. air filter has been changed or is clogged

Posted on Jun 17, 2009

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SOURCE: I need tuning specs for my 1982 suzuki gs 750.

You need to fix the fueling first - without fuel it won't run!
Your other problem sounds like an air leak - either the manifold or the carb. Check by spraying WD-40 or CRC at the manifold and carb join while the bike is running - if the revs change (either up or down) you have a leak.

Posted on Jun 29, 2009

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SOURCE: 81 xj650lh midnight maxim black exhaust, sooty plugs keep fouling

hi,fairly common problem with modified exhaust,start with the pilot screws,turn right in untill the screws are firm then back out 1 and 3/4 turns,this is a fairly standard rule of thumb that will get most things going,as far as the jets go,the original size would be a good starting point,but you should only need to go up 10-15 sizes to compensate for the exhaust mods(ie stock might be 127 may need to go to138 or 140 etc),the other thing that i would recommend is getting hold of a set of damped carb balancers these will enable you to get the mixtures and carb balance dead right,they are relitively cheap and easy to use and will have paid for themselves the first time you use them.(i regularly get 4-8 sometimes 10-11 extra hp over stock by tuning the carbs up properly).hope this helps

Posted on Jul 06, 2009

  • 10 Answers

SOURCE: rebuilt all four carbs cleaned and replace needle

With Mikuni carbs, the idle circuits affect engine performance up to 3000 rpm under light loads. If the idle circuits are restricted (by fuel gum, rust dust from the tank or dirty fuel, the results will be 1) the engine will run with "choke" on. 2) poor or no throttle response below 3000rpm,3) back firing and missing on the effected cylinder(s). Cure is to blow out the idle circuits and idle screw adjustment jets with several applications of carb cleaner and compressed air. Failing that, strip the carbs.

Posted on Mar 23, 2010

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Carb needs to be rebuilt, new needle and seat also float fuel level is critical.
after uninstalling carb remove fuel bowl turn carb upside down to verify float is parralell (level) with carb body if not adjust tab on float so it is clean all small orfaceses and jets.

Aug 09, 2014 | Cub Cadet Garden

1 Answer

Were is the starter relay in my cpi sm 50?

Hi, Anonymous and the usual suspects are:
1. Ignition Switch not in the "ON" position.
2. Engine Run Switch in the "OFF" position.
3. Discharged battery, check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
4. Bank angle sensor tripped and ignition/light key switch not cycled to the "OFF" position and then back to the "ON" position.
5. Faulty starter button/switch.
6. Faulty jiffy stand or clutch pull in switch/sensor.
7. Security alarm needs a reset.
8. Starter control circuit, relay, or solenoid faulty.
9. Electric starter shaft pinion gear is not engaging or over-running starter clutch slipping.
For more information about your issue and downloads that you will need please visit the websites below. Good luck and have nice a day.
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1 Answer

Cpi with 80cc big bore kit but it does not rev cleanly and wont go past 6000 revs. we are running it with a 21 mm carb. any ideas ?

Hi, Anonymous and the usual suspects are:
1. Severely drained or faulty battery.
2. Faulty regulator/rectifier or high output coil.
3. Faulty power valve, solenoid or installation.
4. Clogged air filter or exhaust.
5. Cracked or incorrect float level.
6. Float needle is not seating.
7. Faulty reed valve.
For more information about your question and free downloads that you will need please visit the website below. Good luck and have a nice day.
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Cpi sm50 what oil do I put in the engine that the clutch works correctly

Hi, Alpinestars sorry you can't find the first and best tool you ever bought for your CPI despair not for a mere $0 you can download another one. For more information about your issue and free downloads that you will need please visit the websites below. Good luck and have a nice day.
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Sep 17, 2013 | 2006 Cpi Supermoto SM

1 Answer

Craftsman dlt 3000 16.5 honda engine will only run if the choke is closed

if it still won't run after cleaning the will need to remove the small jet inside the bowl that allows vaporized gas to be pumped into the is very small you will need a needle or something similar to usualy is next to the bowl float and is vertical to the carb..good luck

May 31, 2012 | Garden

1 Answer

Cpi Sm Gearbox Oil Query

Hi, Hartley_t_07 for this situation I would call my local dealer or reputable shop's service/parts department and inquire about any possible quick fix, answers, or parts inquiry. If necessary, transport your bike to the dealer or shop and have a professional technician take it for a test drive, if it is in running condition, and give you a written estimate of repairs and answer any specific questions you may have about your problem. For more information about your issue and free downloads that you will need please visit the websites below. Good luck and have a nice day.
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Apr 15, 2012 | 2006 Cpi Supermoto SM

1 Answer

My cpi gtr 50 won't take in fuel i've cleaned the carb n the fuel but nott'n happens line

Hi, Kaleovidinha always check the fuel flow first to isolate the problem area otherwise the usual suspects are:
1. Fuel tank empty.
2. Fuel cap or fuel tank not venting properly.
3. Fuel filter clogged with rust or dirt.
4. Fuel valve/petcock not in the on or reserve position.
5. Vacuum line to fuel valve cracked, broken, pinched, or missing
6. Fuel valve/petcock clogged or diaphragm cracked, cut or torn
7. Fuel line from the fuel valve to the carburetor or fuel pump clogged, cracked, pinched, bent, broken, or missing.
8. Fuel pump not working
9. Fuel line touching cylinder or head causing fuel to boil and vapor lock, repair by rerouting and wrapping line with convoluted tubing.
10. Carburetor inlet clogged.
11. Carburetor float or needle and seat stuck.
12. Carburetor not venting properly overflow line or bowl fitting clogged, pinched, or bent.
For more information about your issue and valuable "FREE" downloads that you will need please click on the blue links below. Good luck and have a wonderful day.
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1 Answer

I have a Sears craftsman lawn mower that will not stay running. The model # in the engine is 12h887-2314-E1. Can you give any suggestion?

Your engine parts list can be found here:

There are 3 different carb variations on this unit.

Primer type
Choke type
Auto-choke type?

On the Primer type with the plunger on the side of the carb the primer bulb gets a pin hole in it that allows air to be drawn through the primer bulb. So the engine will start an then die after priming.

On the Choke type carb debris in the bottom of the float bowl AND bowl nut will cause this.

On the Auto Choke type there is a diaphram under the carb that can get damaged and allow airflow where there should be fuel flow.

I am pretty sure that your mower has the float bowl on it. remove the bowl nut... take some carb cleaner and spray directly up into the hole the bowl nut screws into and clean it. Then also spray around the float needle.

If your still having problems.. just fro grins remove the fuel supply line to the carb and check for fuel flow. If there is little or no flow either the fuel slector is off or the fuel tank outlet has debris covering the tank outlet hole inside the gas tank.

Thanks for using FixYa.


Jul 04, 2010 | Garden

2 Answers

Sluggish throttle on start of the cpi sm 50cc 2006

this sounds like it has a blocked jet in the carb or the chock is not working right or maybe a low flote level

Jan 18, 2010 | 2007 Highland Supermotard

2 Answers

Hi i have a drz 400 sm which will only start and run when petrol tap is in the prime position any help would be great

USA vs.UK. > I think you are saying the bike will only run with the choke on. Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, ( not all bikes have a water trap bowl ).

Drain the carburetor. There should be a screw on the lower side of the carb float bowl. Remove the screw then replace it after the fuel drains. Turn the gas back on and wait a minute for the carb to fill with gas. Install a new stock NGK spark plug and try to start the engine. If the bike doesn't start and run properly then shut off the gas and remove the carburetor from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Remove the idle screw and the air screw on the outside throat of the
carb and spray into the screw holes as well.
Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two screws down. Only screw these in until they LIGHTLY seat. Now turn each screw one and one half turns outward. Put the rest of the
carb back together, clean the air filter and install the carb. Let the float bowl fill then start the engine. This process should get you back on the road.

P.S. What do ya'll mean when you say " the bike is on a D plate ". Different letters are used. I am in Dallas Texas USA

Please rate this solution. Cheerio!

Apr 20, 2009 | 2007 Suzuki DR-Z 400 SM

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