Megacycle or Web cams - how much do they typically cost for a 4 cylinder bike?

[Chuck78]

Any idea how much Megacycle cams for a GS750/850/1000 8 valve (2v/cyl) cost?

The local vintage japanese salvage shop Rice Paddy got me all excited saying they bought a lot of parts from someone, and there were some GS750 Megacycle cams in the box still. Turns out megacycle lists them as 1979-1986 GS750/1100/1150 cams, the 79 is misleading, they are TSCC 80+ cams.

I looked into the numbers in the catalog, and my buddy Grant at the shop called Megacycle for recommendations for me. The stock GS750 cams are pretty wild at 280 degrees duration, holy smokes! No wonder I have more trouble getting a good idle on them than any other bike I work on! The lift is only about .302" or so stock.
The Megacycle cams offer substantially more lift at around 254/250/261 degrees duration, and .354"/.410"/.380" lifts respectively. What I just learned is that the Megacycle cams will have less low lift duration but substantially more high lift, and the overall duration is shorter, which traps more of the actual compression in the engine, effectively increasing the dynamic (actual, or is it static?) compression ratio substantially. Seems like it will idle better and make more power everywhere overall. now dropping a big chunk of change on a set of cams sounds a lot more appealing, especially considering how the stock cams were mainly designed for high rpm at a sacrifice to low rpm power, and they don;t even have a radical amount of valve lift for a stocker.

[Chuck78]

My buddy at the shop and the awesome tech lady at Megacycle both were steering me towards the 381-70:
.380"/.380" 261/261 duration 107.5/108.5 lobe centers. They said the step down has 9 degrees less duration but substantially more lift at .410" and will wear down faster and require more frequent oil changes.

They were going to check on pricing for me with the shop owner, but he said retail prices were $440 w/core for the cams and $75 for the valve spring kit. any idea how much places sell these for so that I know how much of a price break I should be looking for when they get with the shop owner on markdown from retail list price?

[cbxchris]

I really cannot remember what lifts and all I ran but my rule of thumb on a street engine was this. High Lift....Low duration.

But I was never worried about duration(lasting long) on anything.......I wanted it fast. I like cylinder pressure.

[GSX1000E]

You don't already have those cams in your 920 Why would you have to change the oil more often? I paid $220 for a pair but that was back in '80. Check and see what Webcams or
APE wants for similar cams and you will see that those are good prices. If you can get them for less... good on ya!

[GSX1000E]

If you want to know exactly how good of a deal your local shop is giving you, ask this gentleman how much he paid for his: http://www.thegsresources.com/_forum...rmance-Rebuild

[trippivot]

send your cores to APE or directly to web-cam you'll get change from a $500 dollar bill. .395" are pretty good cams. (no other mods needed) at .425" you will need shim under buckets / retainers / springs and barely clearance the cam cover some.


108/108 LC and your idle will be smooth and fantastic-- bully to faster wear and oil changes - break them in like the instructions say - there is a coating that has to heat up and smear off.- use oil high in phos and zinc -- like (brad penn oil) - I use spectro but lets not start that discussion - too many petro engineers with no field experience.

[GSX1000E]

Don't forget that you need to clearance the cylinder head for cam lobe contact.

[Big Jay]

http://gszone.biz/cams.html