OzVMX Forum
Marque Remarks => Honda => Topic started by: Swiss on February 13, 2012, 10:25:05 am
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Any of you guys have any experience with the Ivan Tighe cams for the older XL250/350 engines?
Thanks,
Swiss
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Sweet as! ;)
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Tim, can you drop me an email?
[email protected]
Thanks,
Swiss
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Dunno about the XLs, Swiss, but I've used the Ivan Tighe 323 grind in me XTs an TTs, one thing though, I send me rockers as well so they can be correctly profiled to suit the cam.
Foss
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So how well did they work for you? Reliability? Problems? Compare to any one else's cams?
Swiss
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I've done 4 motors, all using the 323 Tighe cam and had no probs whatever, I've found the workmanship excellent and very good reliability, there are wilder grinds for the Yams , but I went for this one on the score of not stressing the rest of the valve gear as much and it worked !.
Slides has raced one of my bikes at Nepean and he would tell you it goes very well !!
Foss
Oh yeah, compared to the Protec cam,which I tried first up, streets ahead in all aspects.
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Melts tyres.
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They are top class work, constructed by professional people that take pride in their work, never had cause to worry. Do contact the companty to discuss your wants ,listen to their advice and always associated items (rockers valves bearings etc )matched to your requirements.
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Tim and Foss,
I understand that they have some good cams. Typically I look for some basic specs and maybe a mention or two about how they perform and maybe compare.
Here is the info that I have gotten from them so far:
"I will have a chat to my brother , if I can find him and see if he remembers any of the power curves or has any info on the engine specs.
The cam profiles are not a problem , I have all the detail on the specs we have used.
If you have a look on our web site , www.tighecams.com.au
In the Honda section , look under the xl / xr 250/500. These use the same basic geometry as the 250 / 350 motorsport engines.
The profile we have had most success with are the 399 and the 356 profiles."
That was followed up with:
"The 356 profile would suit the mods you have well,
My brother seems to think that was the profile he used when he raced motorcross on his.
If you send a camshaft , we need about 1 week to turn it around for you ."
The problem that I have is with some of the words used like "same basic geometry" and "seems to think that was the profile"..
The mods I listed were: 486cc bore/stroke engine with +3mm os valves, porting, 40mm + carb, large tuned megaphone exhaust, just my play bike!
So I am looking for info like: Good top rpm cam but soft down low? 356 pulls more rpm than 399? Much stronger bottom and mid range than the other cam etc.. Extra exhaust lift/duraton makes up for restricted exhaust ect... A friend in AU has one of the 356 cams which the XL/XR500 cam specs says has .500"/12.7mm exhaust lift. He just measured it and it gave him .465"/11.8mm lift not .500/12.7mm lift as listed in the specs? Quite a bit of difference? Listed as a Speedway cam for the XL/XR500. That is why I was hoping to find some riders who had raced MX or Speedway that might have run the bigger cams and how they ran for them. The 356 cam uses a LOT more exhaust lift and duration than most cams that I have seen for the XL350 Hondas. Most of them use less exhaust lift/duration than intake. The "modern" 4-v MX designs are actually using smaller exhaust valves in comparison and less exhaust timing on them so I am wondering just what the big numbers for the exhaust are looking to make work?
I am not putting down them or their cams, we just haven't found a satisfying level of communication yet!
Swiss
Swiss
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Let me just say there workmanship is excellent but as far as listening to the buyers needs/instructions of what they want is pretty ordinary ,I bought a billet cam from Ivan Tighe a few years ago for one of my Honda's, I supplied a brand new discontinued popular aftermarket cam for them to copy the grind, the lift etc as thats what I wanted for my motor, in turn I got a completely different grind billet cam from the one I supplied them to copy ???. When I questioned them they told me that there grind cam was better than the aftermarket cam I supplied as there brother used to use this grind cam on his race bike when he used to race WTF :o.
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I think they are reluctant to say what improvement in performance you'll recieve from this or that Cam is because there are too many other factors that come in to play when setting up an engine.
eg - Carb, Exhaust, Gearing, Nut on Handlebars.
Maybe the Griffith Mafioso could help you out here, they've got the fastest & most reliable early XL's I've seen.
But if they told you their secrets, they'd have to kill you. 8)
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Well, Griffith can email me directly or send me a personal post. No way that I can come across the "big waters" to compete with them so they aren't taking a chance on giving away secrets. HA!HA!
It still helps to be able to compare what one set of cam specs does for an engine compared to another cam of their own design. Not asking for comparisons between Megacycle and Webcam and theirs?
Swiss
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they should have duration specs at 50 thou valve lift coz till then theres nothing happening either coming or going from the motor.a big duration cam at total duration degrees could be a little cam with big soft on valve train opening and closing ramps,on the other hand it could be a kick arse cam with short harsh opening and closing ramps and wear your rocker arms out fast.best way to chose a cam is get the 50thou valve lift specs and decide from those figures only.another good thing is degrees of lobe seperation for good intake vacum,too much and it will run like a pig.
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Well, here is the cam spec chart for the XR250/500"
Ivan Tighe #516X
In Lift .412” Exh Lift .412” Duration In 280° Duration Ex .280°
Lobe C IO-30btdc/IC-64abdc/EO-70bbdc/EC-30atdc
Ivan Tighe #356
In Lift .435” Exh Lift .500” Duration In 286° Duration Ex .294°
Lobe C Speedway IO-41btdc/IC-75abdc/EO-72bbdc/EC-34atdc
Ivan Tighe #399
In Lift .412” Exh Lift .412” Duration In 304° Duration Ex .300°
Lobe C Speedway IO-50btdc/IC-70abdc/EO-79bbdc/EC-45atdc
I tried to copy/paste the chart from the web site but it loses all formatting and is unreadable. So here is the list that I put in my Specs. pages for the engine.
This should be the web page for the XR250/500 cams, but as I said, a friend measured his valve lift on a #356 cam for the XL250/350 and it showed almost a mm less lift?
Swiss
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http://tighecams.com.au/bikes.htm
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OK, after doing some further research and checking, I think that the #356 which is listed as a Speedway cam would be good running with 14-1 or 15-1 compression ratio and Methanol. Same basic conclusion for the #399 cam. Their really long duration numbers mean that they will work with the high compression pistons, but would give a lot less performance with a lower compression piston on gasoline. Main reason would be the effective compression ratio from the extended duration. The big lift on the exhaust lobe of the #356 cam I am not sure about yet. Seems like it would basically compensate for a poor exhaust port design or smaller exhaust valves or maybe a restrictive muffler system? Here in the USA we run a lot less Methanol because mainly the racing classes typically don't allow it. Some do but not all.
Swiss
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If you want good customer service and good communication, talk to Phil Joy camshafts in the uk
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agreed ...