XL500 general opinion and mods

[gerpster]

Was wondering what the general opinion is regarding the 1979-81 XL500S, esp. versus the current interest (hype, money) for the XT/TT500 of the same era.

Is the XL overlooked, under rated or just a big lump? I was thinking that surely the 4 valve head and Honda engineering would more than match the XTs of the era.   

Was the balance chain / shaft a mistake and what about the 23 inch front wheel?   

What about mods such as....
Can you use a 21 inch wheel on the front for any improvement or does this change the geometry too much?

Does removing the balance chain (and shafts??) make any difference performance wise?

[squirtmoto]

Hi Greg,
Had a little to do with theese babies, you know they did a genuine 100MPH std trim not bad eh, not too many XT TT 5 hungies did a few mods are
definately swap the whole front end any CR 82-84 are the go, the rear swing arm can be changed using either a RM C-2,N or T or CR450/480 alloy jobbies a few mods are reqd. use a pair of twin OHLINS shocks and try to keep the SALR  ( swing arm lever ratio) the same as the RM, Maico or Huskies.
Also try to keep the steering angle at 27-29 Deg.
these engines are tough and can win any race but to gain more
38mm Mikuni carb, use a propper air box and not a "pod" filter.  Resonance is the key here, if you don't the thing will "POP and Fart" all day!!
Mild port job, just clean up arround the guides and manifold junctions. remove .040" off the head and increase CR to 11.5:1 check valve to piston clearence and correct if hitting. Get your local engine tuner to give the valves and head a 3 angle regrind. big gains here
regrind cam to suit all engine mods, porting, carb and exhaust. Kelford Cams Qld fast cheap and know there shit!
Exhausts are very important and if you choose the wrong way it will rob the engine of power. consult a good engineer here and don't be a tight arse , this one thing will effect the power more that all the mods.
you can remove the CB shafts, but you'll get heaps of vibration through the bars, using rubber dampened tripple tree will help, makes the engine a bit snappy though!
remove as much crap off the bike as possible to lower the weight.
Sound like a lot of work, but it will make a HL beater any day!! and less than half the cost!!

Cheers Big Bill.

 

[gerpster]

Wow thanks Bill!!   

Yeh they seem very under rated to me. I think I just cornered the market on XL500s as i just picked up 2 on ebay....oops!!!   

So soon there will be 3 in the shed!!! Intention is to have a 'nice' one and a track one and 1 for parts. All 1980-81 models i think.

Anyone have a 1979 tank in decent shape?

[Tony T]

Hey Greg
Firstly, let me clarify that I've never owned one nor do I have any particular knowledge about these things.
However, I would expect that they are quite underrated. Especially going by what Mr. Squirtmoto was saying.
The biggest advantage in going to a 21" front wheel would have to me the choice of tyres available and I reckon I've seen a few bikes built with these engines in old VMX magazines. So they must have something going for them.
I remember wanting to buy a secondhand one in '82 but ended up with a 250 for the cheaper rego.
Good luck with it and remember to keep us posted with the odd photo. 

[LWC82PE]

ive had a bit to do with a 82 model. the key is to use good oil and regular oil changes since they dont have a proper oil filter. they still have that cenrifugal oil filter. like the first XL's. i think there are advantages of fitting XR/FT parts, the same as fitting TT/SR parts to XT's. i think the XR heads are probably better than the XL. if yourgonna go really wild look into getting a big fin conversion done on the head. ballards used to do this.

geepers 160kms? they must be geared very high. i recently put a wiseco 630 kit, and full staintune exhaust and rejetted the carby on a 94 XR 600 and then also went a few sizes smaller on the back sprocket as it was geared quite low from standard and i had it up to about  148km and i dont think it was going to go much faster than 150. it felt like it had heaps of grunt but i dont think it was gonna get 160 out of it unless i put an even smaller rear sprocket on the back and gear it for desert work.

[Tony T]

The '82 model had pro-link rear and very different styling.
No idea if the engines were much different though.

[LWC82PE]

yeah pro link but the 82 motors are still the same. they dont have the later RFVC head or anthing like that but they may have a slightly more tuned motor?

[Graeme M]

I owned a few XT/TT500s, a 1981 XL500 and a 1983 or 84 DR500, so I have a bit of experience in what they are like. The XL was definitely the better bike in the bush. It handled better and had better suspension, although the DR steered real nice. The XL was a better streetbike too, although I can't say mine did 160. But the TT500 still had the engine I like, once it was made to breathe. They just have a more grunty feel, plus the TT engine looks miles better - to me anyway.

All that said, I hated the 23" front wheel on the XL which always felt a bit vague and was hard to get tyres for.

I would say the XL was probably the pick as a decent dirtbike and with good tyres and shocks I reckon you'd have a great Evo bike for MX and DT.

BTW I should mention that I could always wheelie the XL much further than the TT - the TTs engine oil backed up through the crankcase breather into the carb... The XL however was an absolute wheelie demon.

Geez I wish I could still wheelie a bike. I used to love the feeling. Now I am flat out getting the wheel a couple of inches off the ground.

[holeshot buddy]

graham your right i used to be able to wheelie forever 
change up through gearbox etc
i could jump on any bike and do this
now i am fuggin hopeless :'(
lucky to go 5 metres
is it old age 
or lack of practice
both

[gerpster]

Ok thanks all..lots of info and ideas there..

Looks like I'm after a 21 inch front wheel..I assume an XL250 21 front from the same era will fit???

[cyclegod]

Ok thanks all..lots of info and ideas there..

Looks like I'm after a 21 inch front wheel..I assume an XL250 21 front from the same era will fit???

Sorry, but the 250S was also afflicted with the 23" front too

[Graeme M]

I think the earlier XLs with 21's would use a different axle/speedo drive setup. Maybe a later XL/XR wheel after they went back to 21. Or, and if anyone knows for sure please set me straight, but wouldn't the XL185 of that model (SA/SB?) be a 21 and use similar setup? Maybe need different bearing/spacer, but could be close?

[holeshot buddy]

we get this at work all the time i think we have about 10  23 inch wheels
you will find like graham said speedo and spacers are different and some brake backing plates as well
its hard to find a good rim they are all rooted
the best option is to lace a new rim and spokes to your hub

a lot of the old wheels have corrosion
and most wreckers charge 80 to 150 bucks
get a price on a new one first before you spend forever looking for a used one
or find a good rim only and lace with new spokes

[paul]

http://cgi.ebay.com.au/HONDA-XL-500-S-1979-ENGINE-Good-one-to-hotup-xl500-vmx_W0QQitemZ350032775523QQihZ022QQcategoryZ43810QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[jimson]

Greg Squirtmoto said up the top of the paige a CR82/84 front end should go right in I think they are disc brake so you can always go faster when its eazy to stop faster  jimson