Xr 500 help

Hi guys new guy here

ive got a honda XR 500 engine in a YFZ 450 chassis (please do not tell me its a bad step i got the xr 500 engine for R2 000 and the Yfz chassis for R4 000 :thumbsup:)

It has a XL 500 head (suppose to give more performance)

Mods : Raptor 700 stock pipe ,cone air filter, redone top end

and the problem is :

1.Once it is revved it does not come down quick it stays at the rev for about 5 seconds then slowly comes back down like there is a extra heavy flywheel.

2.The plug is a light brown color

3. Does anyone know where the fuel /air screw is ? (its the model with a single carb ) 82 model i think

4. Does anyone know of a electric starting system for it ?

thanks

intake manifold leak

my 200R had a similar problem, when you had no throttle, the revs would climb.

It was a result of a worn needle and slide.

Id be fully rebuilding the carb, and replacing the inlet manifold.

Goodluck!

Could be as simple as sticky throttle cable...

For an electric starter, you would have to fit the bottom end from an FT500. This is a major undertaking. Better off buying another bike with starter motor...

Do a search on YouTube for "kick start a XL500R" to learn how to start these bikes without getting hurt. It is obvious when you know, a royal pain when you dont.

Could be as simple as sticky throttle cable...

For an electric starter, you would have to fit the bottom end from an FT500. This is a major undertaking. Better off buying another bike with starter motor...

Do a search on YouTube for "kick start a XL500R" to learn how to start these bikes without getting hurt. It is obvious when you know, a royal pain when you dont.

Im using the Yfz 450 thumb throttle ,but it was in a xr 500 chassis and did the same thing .the revs will not come down immediately .the guy i bought the bike from let the carb sit outside for 5 years . its rides fine but when it is reved with no load ...

is the plug suppose to be light brown ?

thanks

For an electric starter, you would have to fit the bottom end from an FT500. This is a major undertaking. Better off buying another bike with starter motor...

Will it lower performance if i do this ?

I have the engine in a yfz 450 and it cant kick start the lever knocks against the plastics and the heel guards .So i might do this if it does not lower performance .

Hi guys new guy here

ive got a honda XR 500 engine in a YFZ 450 chassis (please do not tell me its a bad step i got the xr 500 engine for R2 000 and the Yfz chassis for R4 000 :thumbsup:)

It has a XL 500 head (suppose to give more performance)

Mods : Raptor 700 stock pipe ,cone air filter, redone top end

and the problem is :

1.Once it is revved it does not come down quick it stays at the rev for about 5 seconds then slowly comes back down like there is a extra heavy flywheel.

2.The plug is a light brown color

3. Does anyone know where the fuel /air screw is ? (its the model with a single carb ) 82 model i think

4. Does anyone know of a electric starting system for it ?

thanks

The FT500 engine would be an easy swap for electric start. Also there is no difference on USA models between XL/XR500 heads. All performance increases were from carb and exhaust. All bets are off when it comes to non USA model specs though. Look for a bad carb slide or cable. The XL carb has a fuel screw IIRC. It should be toward the head side of the bowl on the bottom. An XR carb has an air screw which should be just above the bowl in a recessed hole on the side toward the back.

Yes, put a FT500 motor in. These are notorious for eating their starter gears.

Note that you wil have 3 complications to solve:

- the oil sump (see photo)

- fitting a battery (for the starter motor)

- the exhaust header from the XR500 79-80 or XR500R 81-82 will not fit the FT500 head (the outlets are further apart on the FT)

There are more depending on what you want your motor to do (fit a kick starter and gear, for when your starter motor is shot or your battery is dead, open sprocket cover, etc.)

XR500ROthers#5396885064892592866

FT%20500%20Motor%2001.JPG

If you do it, please share your experiences here. I also have as a project to get this done (I have the motor already).

I think there is article of VMX Magazine with a C&J XR500 fitted with a FT500 motor. Not sure it ever actually worked, the article was made before the bike was complete.

For performance, as an other poster says, there may not be any difference. FT500 was a popular flatrack yoke. Some pushed it to +60HP !! Start with a good carb.

By the way, if I remember well, the crankshaft in the FT500 is lighter. So it will probably rev better with more high end power.

FT%20500%20Motor%2002.JPG

And the FT500 is 12V, the XR500R is 6v

Thanks eric138

i did some research and found that these cranks come in three pieces

can i get the one end with the starter gear and fit it into the xr 500 or the complete crank ?

and find a cover for the side ?

then i dont have to worry about the sump and exhaust headers

can you post more pics on how the starter is mounted ?

Thanks eric138

i did some research and found that these cranks come in three pieces

can i get the one end with the starter gear and fit it into the xr 500 or the complete crank ?

and find a cover for the side ?

then i dont have to worry about the sump and exhaust headers

can you post more pics on how the starter is mounted ?

and do you know of better performance carbs?

thanks

I dont have any more pics. The motor is packed in a box 10,000 miles away for now, sorry.

I think you should check the parts on a site that has the microfiches to check interchangeability, like cmsnl.com.

I wonder if you may need to replace the upper motor case also: this would mean taking apart the whole motor...

One thing I know that you should watch:

the XL500R right side cover is different from the XR500R. It has one less fitting bolt above the gear shifter and the side covers are NOT interchangeable. See photo under. If the FT500 has the same cases as the XL500R, then I am afraid it makes things slightly more complicated...

IMG_20100708_182829.jpg

XL500R side cover on a XR500 (XL500S or XR500R) lower motor case. See the gap above the gear shifter...

15e5_3.JPG

Another photo of a FT500 in case it can help.

The FT500 engine would be an easy swap for electric start. Also there is no difference on USA models between XL/XR500 heads. All performance increases were from carb and exhaust. All bets are off when it comes to non USA model specs though. Look for a bad carb slide or cable. The XL carb has a fuel screw IIRC. It should be toward the head side of the bowl on the bottom. An XR carb has an air screw which should be just above the bowl in a recessed hole on the side toward the back.

You're forgetting about the '81-'82 XR500R with the reed block. The XL500s never had it and depending on who you talk to the reed heads were down 1 to 3 horsepower on top compared to the non-reed heads. :smirk:

I dont have any more pics. The motor is packed in a box 10,000 miles away for now, sorry.

I think you should check the parts on a site that has the microfiches to check interchangeability, like cmsnl.com.

I wonder if you may need to replace the upper motor case also: this would mean taking apart the whole motor...

One thing I know that you should watch:

the XL500R right side cover is different from the XR500R. It has one less fitting bolt above the gear shifter and the side covers are NOT interchangeable. See photo under. If the FT500 has the same cases as the XL500R, then I am afraid it makes things slightly more complicated...

IMG_20100708_182829.jpg

XL500R side cover on a XR500 (XL500S or XR500R) lower motor case. See the gap above the gear shifter...

15e5_3.JPG

Another photo of a FT500 in case it can help.

Hi

the other pic of the ft500 has that blue hose mine also has one but it does not have a oil cooler it just goes from the top to the bottom ....

What part of the motor gets cooler oil like that in the FT500 ?

Thanks

You mean yours has a hose that goes from bottom to the top of the engine side cover? Is it a flexihose or a solid one? It probably already marginally helps cool the oil down a bit. It either bypasses or complements the oil channel inside the cover.

There has been considerable speculation over the years over the need or not for an oil cooler on these motors. They get very hot indeed, although I have never seen actual measurements. I have not seen measurements on motors with coolers either to confirm that they are actually effective.

Then there is the impact of oil temperature on performance and wear: way beyond my competences, but I hear that high temperatures are bad for both...

One down side of the oil cooler I think is the fact that when starting the motor cold, it will take more time for the camshaft to get lubricated as the oil has a longer journey to travel from the sump to the top of the engine. Unless of course there are no-return valves installed I suppose.

A picture of your set up would help.

By the way the XR500R (was a 550cc) that won the Paris-Dakar rally in 1982 (by Cyril Neveu) had an oil cooler (it also had a unique side cover and many other trick bits...)

a215361_1.jpg

neveu_82.jpg

You mean yours has a hose that goes from bottom to the top of the engine side cover? Is it a flexihose or a solid one? It probably already marginally helps cool the oil down a bit. It either bypasses or complements the oil channel inside the cover.

There has been considerable speculation over the years over the need or not for an oil cooler on these motors. They get very hot indeed, although I have never seen actual measurements. I have not seen measurements on motors with coolers either to confirm that they are actually effective.

Then there is the impact of oil temperature on performance and wear: way beyond my competences, but I hear that high temperatures are bad for both...

One down side of the oil cooler I think is the fact that when starting the motor cold, it will take more time for the camshaft to get lubricated as the oil has a longer journey to travel from the sump to the top of the engine. Unless of course there are no-return valves installed I suppose.

A picture of your set up would help.

By the way the XR500R (was a 550cc) that won the Paris-Dakar rally in 1982 (by Cyril Neveu) had an oil cooler (it also had a unique side cover and many other trick bits...)

a215361_1.jpg

neveu_82.jpg

Hi it looks like this ....

And another thing i wanted to ask you is the way the motor is mounted in the frame is the oil pickup ok the way it is laying ?

sorry for the bad pics

http://s1130.photobucket.com/albums/m536/Yfz500/?action=view&current=IMG00034-20110417-1403.jpg&jwidget_action=album#!oZZ4QQcurrentZZhttp%3A%2F%2Fs1130.photobucket.com%2Falbums%2Fm536%2FYfz500%2F%3Faction%3Dview%26current%3DIMG00034-20110417-1403.jpg

http://s1130.photobucket.com/albums/m536/Yfz500/?action=view&current=IMG00034-20110417-1403.jpg&jwidget_action=album#!oZZ2QQcurrentZZhttp%3A%2F%2Fs1130.photobucket.com%2Falbums%2Fm536%2FYfz500%2F%3Faction%3Dview%26current%3DIMG00036-20110417-1403.jpg

I my opinion the only reason why somebody would have to the trouble of fitting this outside oil pipe is to fit an oil radiator.

The position of the motor should not matter too much, so long as your oil pump remains soaked.

I my opinion the only reason why somebody would have to the trouble of fitting this outside oil pipe is to fit an oil radiator.

The position of the motor should not matter too much, so long as your oil pump remains soaked.

Hi eric

thanks for your help but there is one more thing

12 volt conversion

ive been looking at the whole net but could not find out how to do it but found this one piece of info :

Check the unregulated AC output voltage of the alternator at about 2,000rpm.It needs to be 24-32 volts AC.If you only have (1) lighting wire coming out of the alternator,you need (2) wires.This is done by disconnecting the internal grounded lighting coil wire.Soldering a new wire lead onto this coil led and bringing it outside to form a (2) lead lighting coil.Then buy a 12 volt negative ground Tympanium regulator/rectifier.You now have a 12 volt lighting system and a 6 volt ignition system.

i have 4 wires coming out of the cover including the ignition wire but never opened it

as you know i have it fitted in a yfz 450 quad ,and i have the regulator / rectifier with three wires

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?VISuperSize&item=250804617973

will it work ?

i am wanting to connect a battery ,lights (tail headlight ),rev counter

and one more thing the gear shifter shaft comes out ,not all the way but when it does it cant select gears

thanks

You're forgetting about the '81-'82 XR500R with the reed block. The XL500s never had it and depending on who you talk to the reed heads were down 1 to 3 horsepower on top compared to the non-reed heads. :thumbsup:

You're right. I've mentally blocked the reed heads existence out of my mind. After having both I would estimate the hp was more like 5-7 lower. Sawing the reed cage off was still 1-3 less than the earlier head. They were absolute turds.

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