[nox11]

Hey guys,
This is my first post on the forum...

I recently bought a 2007 CRF450X over the net - saw the pictures, communicated with the seller, and all seemed pretty good.

The guy used the bike on his farm - allegedly no hard riding, no bike knowledge, and serviced by the local farm (service anything that has a motor) mechanic.

I got the bike on a good price - and on the word that the bike is reliable, easy starting and strong as an ox, with a massive bevy of photos, made payment for a machine that I have not yet ridden.

There's my mistake I know, so you don't have to point it out again...

The bike was delivered to my place dirty - and not washed and more than anything it pissed me off. If I sell something, I clean it really well before the buyer collects - it just shows decency and pride in whatever you have.

Before I digress...

The bike was extremely difficult to start, the previous owner claims he did not even know the bike had e-start, and so he has always been using the kick starter.

It took me 150 plus kicks (true story) to get it fired up the first time - and by this time I was dead tired. After idling it kicks up after 2 or maybe 3 kicks.

Bought a new battery, e-start spins up, but does not seem to do enough to start the bike.

Changed oil, filters and put fresh fuel in.
Cleaned the carb.
Cleaned the air filter and re-oiled.
Stripped the bike and did a decent scrub job on everything.

The lights were not working and so I re-did most of the wiring, changed bulbs and tail light and installed a DRZ EZ wire kit with indicators in the process.

Took the bike to the shop - had the valves re-shimmed - as I thought this would sort out the starting issues.

Rode it home from the bike shop and that was the last time the bike rode.

It does not want to start - after 100+ kicks it will fire up, with a massive backfire and die immediately, a couple of times of this briefly starting and then dying - and I can't lift my leg with my boot anymore to kick the thing, and so I just give up.

When the bike rode (the 3 times I rode it), it was potent - did not feel lacking in power at all.

The kickstarter has since without riding it anymore (cant get it started) became a lot less effort - feeling like the compression is dropping or has dropped immensely.

Decided to check compression this morning - and there's almost no compression.

With the throttle open - kicking it - I only get 50-60Psi on it...

mmm, what do you guys think? Top end? Or could this be a timing issue? Or something different altogether?

I have little experience working on 4 stroke bikes, and don't want to mess about with something that I can't fix.

I've rebuilt air cooled 2-strokes, and done the minor maintenance on 4-strokes, but not engine. My workshop space is limited along with few tools makes for a touch and go situation.

Thanks!

[driver3]

"It does not want to start - after 100+ kicks it will fire up, with a massive backfire and die immediately, a couple of times of this briefly starting and then dying - and I can't lift my leg with my boot anymore to kick the thing, and so I just give up.

When the bike rode (the 3 times I rode it), it was potent - did not feel lacking in power at all.

The kickstarter has since without riding it anymore (cant get it started) became a lot less effort - feeling like the compression is dropping or has dropped immensely. "

This is almost identical to what happened to me. At first it would start, but only with kick start. Then after a few rides I couldn't start the bike to save my life. Check your valves, they are most likely not within spec, specifically your intake valves. I also re-jetted the carb using a jd kit, didn't help. I will say, when the bike was running, it felt ok.

I ended up doing the piston, rings, timing chain, and had CRFsonly do the head work adding the stainless valves and cnc work. It's going to take some time and cost you some dough, but now my bike starts cold on the first try. I have 60 hours on it since the rebuild, everything is perfect, after the first shim from the rebuild, nothing has changed.

I guess there is a chance it's just the piston - maybe someone on here can give you hint to see how you could tell if the head has ever been done.

[450man574]

Compression will only be 50-60 PSI, as there is a Auto Decompression on it. Are you Starting it in the right Order? Choke, 3 hits of the throttle, Bring it up to compression and Firm Kick? DON"T Touch the Throttle when kicking.

[JimDirt]

Tell us specifically what your starting procedure is , step by step , if it has spark , has fuel and has compression , it should run , when starting it with the E-Start , is it cranking real slow ?? , did you ADD fresh fuel , or DRAIN the OLD fuel THEN add FRESH fuel ? , there are several possibilities it could be , and its going to take some specifics to narrow it down

If you have a Allen Wrench to remove the engine plugs on the left and right side , you will see timing marks , along with removing the valve cover , you can determine if the timing is on

When the marks on the cam gear is flat across the head (level), with the cam lobes facing about 2 O-Clock when looking from the left side of the bike (lobes facing the rear of the motor) and the Arrow on the right side behind the large plug is lined up from the gear and case , and you can see a mark in the small hole on the left side plug , then you should be in time

Now would be a good time to re-check the valve lash , it should be from 0.005 - 0.006 on the intake , the Exhaust should be 0.011 , and the Auto De-compressor should be 0.014

Compression should be 58 psi when using the E-Start (cranking for 4-7 seconds holding at full throttle)

This should get you started in narrowing down the issue

[nox11]

450man574 - Tried that so many times, no luck!

JimDirt - Will the Auto decomp work when kicking and when using the elec start? Compression seems similar - but the elec swings the engine rediculously slow - even with a brand new fully charged fresh battery. (I've checked the exhaust for back pressure - the engine does swing with the elec - just very slow).

Valves were done 10minutes runtime ago - I only rode the bike home from the shop.

The gas in the tank is all fresh 95 unleaded.

My starting procedure that normally worked - choke once, kick once, prime (one hit of the throttle) and kick again without touching throttle - worked in the beginning - and even the last couple of times that it breathed fire - that is the procedure that got it running - par the choke. I give up on the choke around 20 -30 kicks in.

The only things that I have not touched yet is the timing - as I'm not uber comfy doing it. Do you know of a how-too video or thread with pics so I can give it a whirl?

Driver 3 - do you have any idea which of the remedies was the winner in terms of fixing the problem?

Thanks guys!

[JimDirt]

450man574 - Tried that so many times, no luck!

JimDirt - Will the Auto decomp work when kicking and when using the elec start? Compression seems similar - but the elec swings the engine rediculously slow - even with a brand new fully charged fresh battery. (I've checked the exhaust for back pressure - the engine does swing with the elec - just very slow).

Valves were done 10minutes runtime ago - I only rode the bike home from the shop.

The gas in the tank is all fresh 95 unleaded.

My starting procedure that normally worked - choke once, kick once, prime (one hit of the throttle) and kick again without touching throttle - worked in the beginning - and even the last couple of times that it breathed fire - that is the procedure that got it running - par the choke. I give up on the choke around 20 -30 kicks in.

The only things that I have not touched yet is the timing - as I'm not uber comfy doing it. Do you know of a how-too video or thread with pics so I can give it a whirl?

Driver 3 - do you have any idea which of the remedies was the winner in terms of fixing the problem?

Thanks guys!

Yes the Auto De compressor works weather kicking or button

EDIT:
Slow turning over with the E-Start would seem that the De-compressor is out of adjustment , that is why i posted valve specs for YOU to double check , dont take the shops word for it being correct , as i said , this will eliminate the valves from the equation , the De-compressor being just 0.001 out will make a difference , so this is very important , and you can do this yourself since the decompressor does not use shims , it is manually adjusted with a screwdriver and a locknut , so all you need is to make sure its at TDC (by verifying the timing marks as i described earlier)and have a feeler gauge and a 10mm wrench and flat screwdriver , it needs to have a slight drag when pulling and pushing the feeler gauge then lock it down and replace the valve cover and try the starting procedure i described below

Try this for a starting procedure

COLD:

Turn on fuel

Pull Choke Fully

Pump Throttle 4 Times

Hit Button or Kick

If all is in spec the bike should fire right up or at least almost start , repeat procedure

You should not have to do this more than twice , or 2 kicks , when kicking , slowly push down on the kick starter with your foot , till you feel the compression stroke , it will have significant pressure on it , then do a full hard kick from all the way up till the kick start hits the foot peg

HOT:

Use button , bike should start right up , do not touch throttle
Kicking , give 1 or 2 firm kicks as described , if it does not start , pull hotstart lever on clutch side , and give firm kick , again with NO throttle



I still highly recommend buying a Service Manual , you can get one on EBay for around $40 or direct from the Honda Dealer for about $50-$60 , its worth every penny and will show with pictures all the procedures needed to do any maintenance or engine or suspension work on the bike , the only thing here would be in the "How To" sections of the forum at the top of the 450X forum and in its own section , you might find something on YouTube , other than that , the Manual is your best bet

[nox11]

Thanks JimDirt,

Will give it a try.

I have the manual, so will have to have a go at it!

Lets see what happens. Will post once I've had a chance to get around to it - may only be over the weekend.

Cheers

[JimDirt]

I edited my post and added some stuff, so please re-read

[nox11]

Great, thanks!

Appreciate it!

[riddler9]

I would also double-check your wiring. If you did not replace the wires, but rather "found power here to power that" you may be causing your own problem. I did something along those lines when wiring up a brake light on a 250X - caused the starter to turn slow by tapping one of the wires the stock tail light used for the ground. Everything still worked, but you would think the battery was dying until I figured it out.

As far as kicking easier, I am not trying to be funny, but I wonder if you just improved your cardio and leg strength by kicking the snot out of it on previous occasions so now it just seems better.

Good luck. I plan on staying tuned in to your progress.

[Back2-2]

The start sequence is as the others have described - but I would take a look at your pitot jet & see that it is not to large of a size. The pilot is the starting jet and larger than required jet will make them hard to start. You can adjust the air screw in 1/2 turn at a time to see if that improves starting before tearing in the the carb to investigate.
When the jetting is correct they start very quickly.

[nox11]

Thanks guys.

My Jetting seems rather odd - I suppose it is set up for the conditions in SA.

Main jet : 160
Starter Jet: 70
Slow Jet/pilot: 45
Pilot screw: 1.75 turns out
Slow air jet: 100
Leak Jet: 70

Black2-2 - what do you think? I must be honest - not very clued up on jetting...

Riddler - I Installed a new DRZ EZ wiring harnass (with a DRC LED brake/taillight) and cut the original taillight wiring off - the new light running from the new harnass via the switches.

[RLPII]

The jetting is driven by the altitude and humidity for basic riding. Check out the "Jetting" section under the 450 X Section: http://www.crfsonly.com/forum/viewtopic.php?t=13468url.
When I rode in AZ, I jetted for 1 - 2,000 feet in elevation and dry conditions:
Pilot: #48
Main: #165
Needle: JD Red, 4th Clip
Fuel Screw: 2 turns out

Here in Nevada I jet for 5-8,000 ft. and dry conditions:
Pilot: #45
Main: #162
Needle: JD Red, 4th Clip
Fuel Screw: 2 turns out

Both set ups work good for me. Without reading this entire thread again, have you put in a new spark plug lately?

Hope this helps!

[Back2-2]

Thanks guys.

My Jetting seems rather odd - I suppose it is set up for the conditions in SA.

Main jet : 160
Starter Jet: 70
Slow Jet/pilot: 45
Pilot screw: 1.75 turns out
Slow air jet: 100
Leak Jet: 70

Black2-2 - what do you think? I must be honest - not very clued up on jetting...

Riddler - I Installed a new DRZ EZ wiring harnass (with a DRC LED brake/taillight) and cut the original taillight wiring off - the new light running from the new harnass via the switches.

Jetting varies so much with altitude, temp, humidity, mod's ect...

The one thing that jumps out at me right off is that you say you have a slow jet #100. ? That seems to be off the scale ?
Stock was a #45, some mod's & you move up to a # 48.

The main has been bumped up from the stock #142 which even without mod's is a must.

You are having trouble starting so I would start with the Pilot / Slow jet and the air screw and just see what happens. Get that dialed in and then see what the bike runs like.
Like Bob said - check the plug also. make sure it is the right plug & decent shape.

[nox11]

Back2-2 - haha, I think you misread the slow jet - the slow air jet is 100, where as the pilot is 45.
I don't have loads of mods - FMF slipon and just opened the top of the airbox.

Re-checked the Valves last night post the shop doing them.(my feeler guages is in 0.05 incraments...in MM)

Intake tolerance: Between 0.10 - 0.14 (the 10 fits easily - the 15 does not even start to go in)- could this be the problem area?!
Exhaust: 0.25
Auto decomp - Right (single guage) 0.60 (so 0.35)

Timing seems OK - when the notch and arrows line up on the case (through the RH nr10 allen key plug), difficult to get clear view behind the frame, at the top two lines on the cam sprocket but the two lines are parrallel or close to - with the case. How critical is it that they are 100%? Maybe I will have to grab the Vernier if it is mission critical.

I re-checked compression - and it seems OK - kicking it I measured 60-62Psi.

The Elec starter does not play along and I only get a semi decent swing from it - not past 35Psi when using it.

I have not tried the plug yet - mine still looks good - and they are quite pricey here...checket that it fires by holding it close to the frame - it seems to have good spark.

Thanks guys, i really appreciate your input!