I am in need of the oil information for a LTR450 race quad. The USF FSAE team is running the motor in their racecar. We have the clymber book with all of the oil info for the YFZ 450, but the LTR450 is different. The YFZ book has all the parts info, the flow of the oil, etc. The motor is used in a completely custom and purpose built car. It anyone has a detailed LTR450 book and can send some scans or pics, or knows where to find detailed information on the oil system, it would be greatly appriciated.

I had the carb off, the fuel on, pulled the throttle cable and fuel squirted from the accelerator pump like crazy (after replacing the worn-out diaphram). I will check it to see when exactly the fuel sprays. Thanks.

Tonight is the last night I am going to try to get it working. If it's not working tonight, it's going to Barney's in the morning.

I just bought a 2007 YFZ 450. It was running strong, but had a very slight hesitation in the low end. It would spudder a tiny bit when dumping the throttle from an idle.

I took the carb off (disconnected the throtle cable, left everything else connected) and removed the float bowl. The bowl was loaded with varnish, had obviously been sitting arround a long time with bad gas. I clean the bowl with carb cleaner. I removed each of the jets and the fuel mixture screw and cleaned them. I replaced the jets tightened to snug, and set the fuel mixture screw to 2 turns out (yes, I didn't count 1st, silly me).

I put it all back together, started it up and it is running very poorly. It sounds fairly smooth on the idle, and if I slowly give it gas, it will accelerate. However, when I dump the throttle, it sputters horribly and just stalls out.

I took it apart again, and found the diaphram for the accelerator pump was dry-rotted some, so I replaced it. I took all the jets out again and cleaned them again. I also put in one of the aftermarket fuel mixture screws that can be thumb adjusted w/o removing anything from the bike (www.outlawracingproducts.com), set 2 turns out.

So I started it back up, same problem. Starts right up, idles ok, if giving it gas slowly it will run up and sound smooth (in nuetral). BUT if I dump the throttle, it's a spudder, choke out and die fest.

I'll take it apart again today to see if I missed anything. Any help or advice would be awsome.

I have a 2002 warrior 350. I was riding at the track when I lost power and got a bad engine rattle. I took off the valve covers and found the lock nut on my exhaust valve had come off. I believe the nut was the rattle, and the screw backing out was the loss of power. I bought a new screw and nut and placed them in. My understanding was the exhaust asjustment for the warrior was 0.006-? so I adjusted it to 0.007 TDC cold. I checked the compression and got 155psi on my old guage. The quad seemed to idle well. It sounded to me like it had a bit of a puffing sound that didn't seem normal (don't know how else to describe it). It seemed to respec correct, so I took it on the street. It had very good power in 1st, 2nd and 3rd gears. It didn't sound completely healthy in the high RPM in 4th and 5th gear. I let off the gas for a second, and when I hit the gas again it completely shut off. After I pushed it home, I took off the cam sprocket cover (which previously everything looked healthy). The cam sprocket turns when I hit start but the cam does not. One of the holes in the sprocket appears to have flexed and I believe the lock bent out and the sprocket is spinning freely on the cam. I haven't done anything else with the quad since I have seen this. The shop guys told me the sprocket would have broke if the valve was adjusted too tight. They told me to put a new sprocket in it and readjust it again.

Any insight on this? I don't want to throw parts at a quad with a problem, but I also don't want to tear apart a top end with 155PSI for no reason. I was going to take the advice and simply order the sprocket and try again, but I just don't see why the sprocket would have broke, and am afraid something greater is the problem. I can't recheck the compression to see if the valves are burnt up w/o it... Advice? Help...

I'm going to be buying a YFZ 450 very soon or I'd just tear it apart and put a hotcam in it. I'm going to keep the bike as a spare/friend bike and want to keep it simple and cheap. It's important to me to make it as reliable as it once was.

Thanks

Thanks for the reply. I'm going to look into that just because it doesn't look right.

I can't find my 3/8" drive allen sockets but I did get the covers off. The adjustment nut came off the exhaust valve. Doesn't look like there was any damage to the engine. I should be back at Croom by next weekend!

I'm having engine troubles. I think it's a valve problem but I have not got that far as of yet. I need a better set of allen's before I can get the covers off.

Meanwhile I had a question about the exhaust. The exhaust where it connects to the head has a phlange on it. On my bike the phlange does not rest smooth with the head. It is about 1/8"-1/4" off the head. The bolts don't tighten down any more. Is there something that is supposed to sit between these parts? Is it suppose to be flush to the head? I know there is a gasket but the gap is pretty big to be a gasket. I figured the gasket is probably at the tip of the pipe.

The bushing for my chain roller is gone. I went to buy a new one. They told me the After Market chain roller would work. It doesn't not fit over the frame pin. The book definitly has the part listed for my bike. I'm wondering if the way to install the part is to cut out the frame pin or something. Barney's wasn't able to provide information on how to use the part they sell. Go figure...

This is the part they sold me... http://www.motoworldracing.com/MSR-Chain-Roller.html

Any info will help. I think I need to cut out the frame pin, which is ok because it's damaged, but I don't want to do that and then find out it wont work. I could still use a stock bushing, but they don't last very long.

Thanks.

Is that everything there is to be contributed?

Thankyou

Hi, I don't visit these forums much but I was hoping for some help. I've done a bit of asking and reading arround and I hear the YFZ 450 is not very reliable. I have a Warrior 350 and I was looking to upgrade. I believe there's ligitimacy to the lack of reliability of the 450, but I haven't been able to determine if the 450 has a bad reputation because built up race bikes are exploading, or if the stock bike is a time bomb too.

So, what I'm trying to find out is if I get a stock YFZ450, will I be able to jump on it every weekend with little maintance? Will the same be true if I put a pipe on it (I wouldn't do any more engine modifications than a pipe)? If the YFZ 450 isn't reliable, is one of the other 450's as reliable as my warrior?

I want a good sport bike that doesn't take a lot of maintance. I want to be able to change the oil and clean the filters, maintain bearings and things like that. I don't want to have to replace the piston and rings 1-2 times a year as I have been told I would have to do with the YFZ450. I may consider a different 450 model even though the Yamaha is my favorite. I do not race but I get out in the fields or on a rough track and dog my machines. So far, my warrior has held up incredibly well (except for K&N filter letting dirt through and burning up my valves. No more K&N for me.) and I will be happy to keep it if the 450 isn't trustworthy.

Like all laws, they are there because someone did something stupid. Croom use to be 100% open with the exception of the main road that runs along the side of I75. The bikes use to run down the roads by the back parking doing about 60mph. They crossed anywhere they felt like as fast as they wanted too. One day, a girl ran her dirt bike into a car. That girl died.

Croom added restrictions on where you can cross the road and they will give you speeding tickets for riding wrecklessly on those roads. The rest of Croom is still open like it has always been. The restriction only apply to the roads and they should, it's too bad a girl had to die before they realized that w/o restrictions people would get hurt.

The restrictions are only applied to the one road that cars are allowed on. The road that follows along side I75, it then turns west and goes directly across to the camp ground. That is hardly restricted riding.

The park is fun and it is worth the money.

Wednesday I bought a Honda XR100. I got an offical Bill of Sale document from the DMV/Tax Collector and filled it out properly. Today I went to the DMV to get a title made (cuz I am a good little boy and title my bikes) and they DMV gave me nothing but problems.

~ I gave the guy the Bill of Sale.
- He proceeded to tell me that I needed to go back to the guy I bought the bike from and get proof of ownership.
~ I asked him why i needed to get that guys bill of sale.
- The DMV guy told me that a Bill of Sale is not proof of ownership.
~ I told him that the bike has never been registered, that ATV's were not required to be registered until 2003-2004, and this is a 2001. I don't understand how I am expected to proof of ownership on a bike the was purchased used from a guy who purchased it used from a guy in Alabama, and has never been registered. I told him there is no MSO certificate, and that it would be impossible to get one.
- He told me that he cannot check registrations from other states (The DMV cannot run a VIN!?!?) and that I needed to call the DMV in Alabama and find out who the bike is registered to.
~ It's not registered!

So I call up my sister who works for the police department and she runs the VIN. It doesn't exist in the system, and the reson being, as I had told the guy, the bike was never registered. Proof of ownership does not exist and therefor cannot be provided. The bike has changed owners only through bills of sale and the VIN check comes back clean.

Tuesday I have to go fight with them again about it. I want my bikes titled. I printed the thing about titles in this post http://www.atvflorida.com/forum/index.php/topic,3447.0.html and that already provides me with more information that I had previously (since the guy at the DMV argued that my XR100 is not an OHV so it has to have a registration).

I know the people at the DMV have no clue about OHVs since most OHVs are not registered. I am open to any experiance with this.

Croom requires more than just the VIN on the bike. They require a bill of sale or a title. Florida did not require bikes to be registered until (about) 2004. most bikes do not have titles so titles are not required. They do require some proof of ownership and a bill of sale is usually enough.

My dad got his Quad in west virgina 3 years ago and never transfered the title from the dealership. They accepted it, so they are not too strict.

With Croom you buy a 1-year pass. It is a sticker you place on the bike. pay once and you good from july to July.

July - September = $60
october - december = $55
January - March = $50
April - june = $45

I think...

Anyway, grab your bill of sale and we'll see ya there.

PS. remember, If you buy a bike 2004 or later, it should have a title.