PlanetMinis Forums banner

I need Ultra head tips.

1543 Views 17 Replies 10 Participants Last post by  cyclerider57
I just slapped a kitaco ultra head on my 88cc big bore from classic honda. It runs great from mid to top but the bottom end bogs bad. Sounds like bur bur bur bur, kind of like a rev limiter. If any one has any tips or has put an ultra head on their bike, let me know, thanks.
1 - 18 of 18 Posts
ultra head

What size carb are you running? whats your gearing?
you may just need to adjust your carb for that head, by the way did you just get a head alone? and how much did you pay for it?
Re: ultra head

mike224 said:
What size carb are you running? whats your gearing?
I am running the 20mm carb that comes with the kitaco 88cc kit. My gearing is 15 37, i know that is not the problem. Its some where in my jetting. Just havent figured out where just yet.
04crf88 said:
you may just need to adjust your carb for that head, by the way did you just get a head alone? and how much did you pay for it?
I already had the kitaco 88cc big bore kit. What I just bought was the Kitaco Ultra Bore Up Kit. Whick is a ultra head with a full race cam, large valves, springs everything you need in the head and a high compression piston. I cant say the price i payed for it cause i am a dealer with classic honda, but it retails for $800. www.hondaminitrail.com
Keep playing with the jetting if its loading up on the bottom keep adj. the

air screw I have the same set up but have the Touring cam in it and have

run both the 20mm carb and I now run the 18mm carb plus a foam air

filter its cold out now so run the bike a little rich use 85 main jet and play

with the clip. Every time you play with It you got to adj. the Air screw and

Idle................. Hope this helps.





OLDSCHOOL
See less See more
if i was u id check the cam timing again and make sure your not a tooth out they doo run with a tooth out but give no top end power have alook . 8)
we ran that head set up with both touring cam and race cam and found it will still have a blurpy bottom end power band even with a 24 or 26 mm carb remember the carb size should match the intake valve size and the Ultra head has a 26 mm OD port and a 25mm valve on the intake side and 21 on the exhuast .



We fixed this problem by running a 20mm carb with jets drilled to twice there size for methanal and it ran like a beast but still burped a little but spanked everything in site .



PS. Classic has the new 117cc SE Kitaco set up now for $1395.00 Lyle had a couple of these air freighted to us from Japan before they were available to the public and man I 'am talking super rocket horse power and performance that beats the 124cc 4 valve head Takagawa set up for thousands less check it out you won't be sorry you did
See less See more
you said you got the ultra bore up kit w/ race cam? that's you problem---the race cam-- you need the touring cam. i found this out the hard way just like yourself. if your bike screams from about 4,000 rpm on up but has a bad flat spot right off idle-- it's the race cam.



and skindonor is right those se 117 kit are freakin insane!!!!!!
On the street the Kitaco 88cc Ultrahead runs best with a Keihin PE24 carb, as the 20mm Keihin will give more low end power, but is too small overall for the application.
I'd be inclined to agree with Motorhead - check that the cam timing isn't out a notch!!
Thanks for all the tips guys. I am currently still jetting on the bike. I just put the 18mm carb on it and it helped out some but still has that bottom end bur bur bur. And I talked to shane a classic honda today and he said that the race cam was one of my problems. I wish he would have told me this before cause I told him I was wanting some bottom end power for MX, but oh well.



Skindonor- yeah that 117 does roll. Classic honda had sent one of their riders (Bean) to a race at an indoor bmx track in Houston, TX. The bike was too fast for the track. I dont want something that fast, I just want a little more than the regular 88.



motoguru- how does your bike run now that you have the touring cam?



oldschool- how does yours run as well?
See less See more
that ultra head you got, you will really be pleased when you get the touring cam in. the touring cam works good for the moto cross application. go try the touring cam and let us know as we will probably be able to see your smile through your writings.
yeh baby the 117 is fast but here in cali our tracks are wide open and thats what you need .



Hey remember that either the touring cam or the race cam is going to give you bottom end power problems it is the nature of the beast . there is so much cam over lap that that sucker is blowing gas back out the carb . try a lower octane gas it burns quiker than high octane this might help if not run methanal with a manual clutch set up it rides like a two stroke but man the power is incredible .



Hey That Bean is a super cool guy and quiker than snot .



PS. I have a ultrahead set up for sale. we converted it to a 118cc on methanal PM if you are intrested
See less See more
motoguru said:
that ultra head you got, you will really be pleased when you get the touring cam in. the touring cam works good for the moto cross application. go try the touring cam and let us know as we will probably be able to see your smile through your writings.


motoguru,



I take it you are affiliated with Classic Honda?
Our head that we designed and ported and polished will beat it! It's only $350.00 complete with a killer cam!

Jim

www.precision-racing-components.com
Hey Jim what kind of head is it?? and man if it spanks the ultrahead for $350.00 I want to sell in my store
G
If it will beat the ultrahead for $350 then I want one. Bigger valves? email me at [email protected] with details.
1 - 18 of 18 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top