XT500.org - Das Forum -

I currently have a stock 82 xt500 engine running a TM36 carburettor, KN filter and a 44mm Exhaust system with supertrapp and 16 discs.

Its been using some amount of oil this summer so now its time for a top end rebuild.

The rebuild specs are.

Wiseco 90mm piston 11-1 compression
49mm inlet valve, stock exhaust and ported head.

I need advice on the rockers, camshaft and springs?

The bike is used for street use and little off-road, but likes to pop wheelies from time to time so i could use some more torque as well.

Best regards

Kasper from Denmark

Hi Kasper,

I would take a 88 or 89 mm Wiseco, compression ratio max. 10:1, works better. As camshaft I would prefer a "FS1", it can be used with the stock springs. But of course, there are a lot other possibilities...

Regards Mambu

I currently have a stock 82 xt500 engine running a TM36 carburettor, KN filter and a 44mm Exhaust system with supertrapp and 16 discs.

Its been using some amount of oil this summer so now its time for a top end rebuild.

The rebuild specs are.

Wiseco 90mm piston 11-1 compression
49mm inlet valve, stock exhaust and ported head.

I need advice on the rockers, camshaft and springs?

The bike is used for street use and little off-road, but likes to pop wheelies from time to time so i could use some more torque as well.

Best regards

Kasper from Denmark

, hello, i would take 89mm

Hi Kasper,

I would take a 88 or 89 mm Wiseco, compression ratio max. 10:1, works better. As camshaft I would prefer a "FS1", it can be used with the stock springs. But of course, there are a lot other possibilities...

Regards Mambu

Hi, Kasper,
I would take a 88 Proxx Piston, because we tempered it and it had 0 deformation.
I would take new Kedo Valves without bigger diameter. and reform the seats.
I prefer the FS1 cam too, but only with hardened 0,3mm shims instead of the 1,5mm stockparts.
It can be used with stock springs.
Thicker downpipes produce a severe loss of power exept you are extremly open in the muffler.
Best is the stock parts, because noise performance usw. Peppmöller or Kedo from the same Fountain can achieve that. Bigger carbs are sensless without porting. Christian can support you.
Regards
Rei97

hello kasper,

first thanks to helmut for the recommendation!

Depending how much money you want to spend i would see following route:

The stock head is a bottleneck (based on my almost 20 years of porting and measuring those heads)
therefore one (if wanted i could also gladly do it) would need to sensibly port the head according to needed characteristics thus components.
I (in my opinion and my taste and experience) would consider therefore:

Megacycle 140 or 130 camshaft and rockers as well as you will need the added valve lift for low rev hi tq applications and a vernier wheel ( hiha or rei97 wheel)
stiffer springs R&D kibblewhite whatever you prefer
ported head with standard size valves and of course recut multi angle seats
free flowing muffler but not necessarily bigger header as you otherwise, depending on state of tune, get flow and exhaust wave disruptions (too lengthy to explain now in short words)
perhaps a TM 36 for better mixture signal on the mixturing tube and needle.
Piston i always loved the US pistons despite what people say but the proxx piston would be perhaps really a good economix choice as it is forged and from my datedd info a woessner product.

Last but not least i would recommend a look at the rockerbox to check for the axlebushings if worn out as else youre risking costly material failure!!!
(in case worn i could also repair these professionaly as i have to do some within the next 3-4 weeks )
Hope that the info helped a little.

kind regards

Christian

kasper,

partially due to my current a little of track mind i did not fully read your post, therefore sorry:

11:wiseco? perfect and i would almost recommend to modify (weld up and mill accordingly) the combustion chamber accordingly .

Supertrapp? perfect although i like the "what will the neighbour say" open cap

44mm header might work but one would need to check and pair it up with selected cam spec

49mm valve? doable but perhaps a hint too large for hopped up street use with 90mm bore.

In case of any other questions keep em coming

Kind greetings

christian

Hi Christian.
Are you still doing headwork?

Best regards

Kasper from Denmark

Hi Kasper,

where are You from in DK?

Regards from Kiel
Theo

Hi Theo,
Kaspers letzte Aktivität war:
Mi Dez 14, 2016 19:55
Du solltest es nicht persönlich nehmen, wenn er nicht umgehend antwortet;o)
Gruß, Fabi