Triumphrat

wildchild · 02-05-2008

Has anybody try to just put in a differnt cam with out the bigger bore kit you would think that it would help alot. Seemed it help alot in the old cars but with the price of the cam does this make it worth it or not. Don't recall seeing any threads on this

mikeinva · 02-05-2008

If you could find a better cam .The only thing wrong with the cams you see offered for our bikes is that the guys selling them dont give spec. on what you are getting like they do on cars. The early 790 stock cams are better then the later 865 stock cams.

Trident_Dave · 02-06-2008

I'm also interested in this. I'm in two minds weather to do this mod or not. I don't want to do a big bore kit at the moment. I also don't want a cam that is going to turn my bike into a top end bike. I still want it to pull like a train from the idle to redline.

Can anyone comment on the different cams out there? How they effects the bikes power band?

Hedge · 02-06-2008

I'm laughing real hard here. The story of my life begins with, "While you have the engine apart you may as well do _______ as well!"
***NOTE*** Enter Internal Engine Modification of choices inside of Blank.

amanger · 02-06-2008

Quote:

Originally Posted by mikeinva

If you could find a better cam .The only thing wrong with the cams you see offered for our bikes is that the guys selling them dont give spec. on what you are getting like they do on cars. The early 790 stock cams are better then the later 865 stock cams.

I think the 790 cams are only better if you spend all your time riding around at full throttle and over 5000 rpm.Having owned both a 790 and a 865 I think the 865 motor is easier to ride due to the power being lower in the rev. range.

mikeinva · 02-06-2008

Quote:

Originally Posted by amanger

I think the 790 cams are only better if you spend all your time riding around at full throttle and over 5000 rpm.Having owned both a 790 and a 865 I think the 865 motor is easier to ride due to the power being lower in the rev. range.

what you feel maybe the extra cc.besides these bikes dont come alive till 5000 anyway.A 904,989,100 OR A 1200 KIT AND 790 cams you will more then the 865 from 2000 to 8000 .let that thing scream its made to.

whatisit · 02-06-2008

You couldn't pay me enough to put my 865 cams back in. To say that 790 cams are only better if you spend all your time at full throttle over 5K rpm is a narrow view. My own view is perhaps pretty narrow as well, since I really don't care about low-end torque. There is a loss under 3500, I've never missed that power for a second. I didn't really notice any difference in power from 3500-5500 where I spend most of my time. But I did notice a huge difference above 5500. That might not be where I spend most of my time, but it is where I spend my quality time. I do have FCR carbs, but no big bore. I got the cams by buying a wrecked bonnie. Dollar for dollar aftermarket cams might be better than new 790 units. If you plan to go big bore and/or cams I'd probably pick the big bore/compression boost first. I just had the cams sitting there so why not...

Bottle_Fed · 02-06-2008

It's true. The stock 360* 790 cams, '01-03, are your best cams out there. In late '03-early '04 they changed them. That is why you haven't seen anything aftermarket for them, and if you have, there hasn't been a comparison dyno against them. To gain lower and mid rpm tq, with a slight trade off for 3-5 hp on the top end, is to advance the exhaust 1 tooth.

Greg

dazco · 02-06-2008

Quote:

I think the 790 cams are only better if you spend all your time riding around at full throttle and over 5000 rpm.Having owned both a 790 and a 865 I think the 865 motor is easier to ride due to the power being lower in the rev. range.

True. The 790 power specs on both bonnies and cruisers shows higher HP and less torque with a peak at higher RPM's. So it's a trade-off. The thunderbike cams basically give you both and then some if you can believe their dynos. They've been accused of not being fully honest in the past, but then someone at BA tried them and said they really did add a lot. The trade-off seems to be an emissions thing because the thunderbike cams have kept the same low torque as the 865 cams but then adds the lost HP the 790 cam had plus about 2 or 3 more from all the specs i've seen on stock twins and the TB cams. It's up to you to decide how true their dynos are, and that one guy who posted several months ago at BA is the only one i've seen who bought them. The big problem i see is cost.the TB cams are stupid expensive. If i recall the last time i looked i think they were around $1300 to the U.S. after shipping and all. I may be off some, but not by much. Then again, if they DO add 10 HP then $1300 isn't really all that bad considering how much some of us paid to get about 7-8 HP via pipes and mods. It's all in how you look at it. The fear i would have is no matter what the dynos say or what anyone who bought them said, i know all about murphy's law, and $1300 is a lot of cash to take a chance on.

Bottle_Fed · 02-06-2008

Daz, your right in relation to the 270* engine. IMO TB has not yet produced cams for the 360* 790's yet, and I think it's because they can't produce a product to out perform them. If they could, some would be out by now, they're out for the 360* 865.

Greg