Some help with build details 98”

[Johnwesley]

Been two years since the last build and have decided to change it up some but could use some help with Tb and cam. Bike is a 05 fxdi 5spd and gets put in touring duty. I don't always have 91 available. Like the last trip the station we stopped at was out of 91 next station only had 87 so a tank full went in and the next station was 60 miles away. Never two up and I'm about 220lbs.

10.5:1 compression With .040hg
Good flowing heads with 1.9 intake and 1.61Ex flowing 290@28
Fat cat with big bore baffle

For the throttle body I'm looking at either the 55 x 1.8 or 58x1.8  not sure which one will be better and could depend on cams

For the cams I am looking at a few different ones the cr595 s&s 585 tman590 possibly the tm625 though my compression my be too much have even look at the rs57

I may be slicing hairs with the cam and Tb but would like to know yours thoughts

[rking1550]

10.5 is perfect for the T-man 625. Ran that in my roadking for years. No issues and I'm  running a carb.  Can't help with the other cans as I have no experience with  them.
As for fuel, you can get some octane boost in little 1 or 2 ounce packages and add to a tank of gas. I never had to tho. And I've ran 87 a couple times when better choices were not available.

[Johnwesley]

10.5 is perfect for the T-man 625. Ran that in my roadking for years. No issues and I'm  running a carb.  Can't help with the other cans as I have no experience with  them.
As for fuel, you can get some octane boost in little 1 or 2 ounce packages and add to a tank of gas. I never had to tho. And I've ran 87 a couple times when better choices were not available.

Thanks for that, I really like being able to have a bike I don't have to baby. If the 625 can run at 10.5 and not be finicky about gas that would be nice. I would ass/u/me it would pull out the top with good flowing heads.

What was your set up in the RK?

[Don D]

There was an older dyno on here with my Pro heads and a 98" and the CR595. Made north of 120 squared IIRC. Tuned by Nick in Texas. It takes 11:1 to run that cam effectively and it won't ping there if tuned right. Would not consider the Tman 625 and the 590 would be a contender at 10.8:1. S&S 585 not usually on my list except for guys that insist on gear drive or easy starts.

[Johnwesley]

There was an older dyno on here with my Pro heads and a 98" and the CR595. Made north of 120 squared IIRC. Tuned by Nick in Texas. It takes 11:1 to run that cam effectively and it won't ping there if tuned right. Would not consider the Tman 625 and the 590 would be a contender at 10.8:1. S&S 585 not usually on my list except for guys that insist on gear drive or easy starts.

I saw that chart and threw the 595 in just because of it. To be totally honest, I'm concerned about pushing the compression up that high. Not that it won't work DJ proved it will in his bike with the way he rides it. I'm just not sure about how it will work for me. That said I haven't ruled them out but not sure I can make 11.1. 10.75 is about the best I can get.

Are you saying not to run the tman cams or not to run them under 10.8?

[Don D]

I am strictly not loyal or against any cam brand. I will use which one is a good match to reach the goal. Compression then adjusted to the cam choice. If I can't hit the number then I punt. The 595 needs that much CR. Lower and it will not be real spunky down low. Pipe choice is part of the equation too. And the heads? 1.8" inlet? My personal opinion I reserve that for a larger valve (throat) head. The 590 will and does work well at 10.7 if that is what you can get to. At 98" I would be using a dome for sure and not milling the cr** out of the heads.

[Ohio HD]

Pulled this one out of the catacombs in the dyno section.

As Max states in the attached thread, you don't need a lot of cam, to make power when the heads are good. As well all of the parts need to work well together. IMHO is this is mainly going to be a touring bike, I'd keep the valve lift to a moderate height, 0.600" or less. Not as much stress on things that way.

Nice broad torque in the 3,000 to 5,000 range. Which is where you'll be 95% of the time on open road. Unfortunately he doesn't state his cranking PSI or static compression. But I doubt it's anywhere over 200ccp. I would guess around 10.5:1 to 10.8:1.   


https://harleytechtalk.com/htt/index.php/topic,88660.msg1012308.html#msg1012308

[Don D]

Here is a little more spirited build. It's all about what you want. Pipe is an important part of the equation too. this build with a fatcat would have a much better torque curve.
https://harleytechtalk.com/htt/index.php/topic,97306.msg1286027.html#msg1286027

[rking1550]

10.5 is perfect for the T-man 625. Ran that in my roadking for years. No issues and I'm  running a carb.  Can't help with the other cans as I have no experience with  them.
As for fuel, you can get some octane boost in little 1 or 2 ounce packages and add to a tank of gas. I never had to tho. And I've ran 87 a couple times when better choices were not available.

Thanks for that, I really like being able to have a bike I don't have to baby. If the 625 can run at 10.5 and not be finicky about gas that would be nice. I would ass/u/me it would pull out the top with good flowing heads.

What was your set up in the RK?

Mine was a 2001 roadking, 10.5 compression,  t-man 625 cam T-man
Older stage 2 head. I cant remember what he was calling them at the time. A 42 mikuni carb DDT ignition and a bub 7. 2 into 1 exhaust. Been on multiple dynos always made 105 to 110 hp and same numbers on torque. And that was a 95" motor.

I would think with efi and being able to tune it better than a carb. You'd be good. But others on here are much smarter and have way more experience than I do. You might be better off listening to some of them .

[Johnwesley]

Pulled this one out of the catacombs in the dyno section.

As Max states in the attached thread, you don't need a lot of cam, to make power when the heads are good. As well all of the parts need to work well together. IMHO is this is mainly going to be a touring bike, I'd keep the valve lift to a moderate height, 0.600" or less. Not as much stress on things that way.

Nice broad torque in the 3,000 to 5,000 range. Which is where you'll be 95% of the time on open road. Unfortunately he doesn't state his cranking PSI or static compression. But I doubt it's anywhere over 200ccp. I would guess around 10.5:1 to 10.8:1.   


https://harleytechtalk.com/htt/index.php/topic,88660.msg1012308.html#msg1012308

That's a good look. Chart making some Hp to boot. He is at 10:1 so the ccp is round bout 195. Looks good but I can't get that low for sure. I do like the curves though.

Here is a little more spirited build. It's all about what you want. Pipe is an important part of the equation too. this build with a fatcat would have a much better torque curve.
https://harleytechtalk.com/htt/index.php/topic,97306.msg1286027.html#msg1286027

That's looks nice with the dip removed just about perfect. I have the fat cat so that "should" help. I am running a 10cc dome for compression and the heads are 86cc. Do you have any graphs of that 590ps2 with a 98?  On the 1.8 inlet that's the recommendation of the porter and he said TB 55/58 hpi. I'm not really questioning him, but he was vague on the cam.

[Ohio HD]

Pulled this one out of the catacombs in the dyno section.

As Max states in the attached thread, you don't need a lot of cam, to make power when the heads are good. As well all of the parts need to work well together. IMHO is this is mainly going to be a touring bike, I'd keep the valve lift to a moderate height, 0.600" or less. Not as much stress on things that way.

Nice broad torque in the 3,000 to 5,000 range. Which is where you'll be 95% of the time on open road. Unfortunately he doesn't state his cranking PSI or static compression. But I doubt it's anywhere over 200ccp. I would guess around 10.5:1 to 10.8:1.   


https://harleytechtalk.com/htt/index.php/topic,88660.msg1012308.html#msg1012308

That's a good look. Chart making some Hp to boot. He is at 10:1 so the ccp is like he round bout 195. Too look but I can't get that low for sure. I do like the curves though.

He says he has "10:1 pistons", but I'm sure that his heads have been machine thinner.

[Ohio HD]

I would speculate about 10.5:1. But that's all is is, a speculation.

[lonewolf]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

[Johnwesley]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

What supporting parts did you run with it?


I call tman and asked about the cams and they recommend as Don did that the 590 would be a better fit than the 625. Especially if I could put it at 10.8. He said the 625 is more of a low mid cam and the 590 more of a mid high cam. If the 590 is run less than 10.8 it would be soft on the bottom, but at 10.8 I wouldn't notice. Based on the above chart it looks to be more mid range than low rpm tq. He seemed to like the 590 at 10.8 over the 625 at 10.6. All that said the above chart looks good

[lonewolf]

What supporting parts did you run with it?

Don's heads, Dragos 2:1, 6cc CP pistons, One of the discontinued Kuryakn 57mm tb's.

[Ohio HD]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

What supporting parts did you run with it?


I call tman and asked about the cams and they recommend as Don did that the 590 would be a better fit than the 625. Especially if I could put it at 10.8. He said the 625 is more of a low mid cam and the 590 more of a mid high cam. If the 590 is run less than 10.8 it would be soft on the bottom, but at 10.8 I wouldn't notice. Based on the above chart it looks to be more mid range than low rpm tq. He seemed to like the 590 at 10.8 over the 625 at 10.6. All that said the above chart looks good

Russel also knows a fantastic tuner.   

[Johnwesley]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

What supporting parts did you run with it?


I call tman and asked about the cams and they recommend as Don did that the 590 would be a better fit than the 625. Especially if I could put it at 10.8. He said the 625 is more of a low mid cam and the 590 more of a mid high cam. If the 590 is run less than 10.8 it would be soft on the bottom, but at 10.8 I wouldn't notice. Based on the above chart it looks to be more mid range than low rpm tq. He seemed to like the 590 at 10.8 over the 625 at 10.6. All that said the above chart looks good

Russel also knows a fantastic tuner.   

My plans for tune is power house dyno in Mo

[Ohio HD]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

What supporting parts did you run with it?


I call tman and asked about the cams and they recommend as Don did that the 590 would be a better fit than the 625. Especially if I could put it at 10.8. He said the 625 is more of a low mid cam and the 590 more of a mid high cam. If the 590 is run less than 10.8 it would be soft on the bottom, but at 10.8 I wouldn't notice. Based on the above chart it looks to be more mid range than low rpm tq. He seemed to like the 590 at 10.8 over the 625 at 10.6. All that said the above chart looks good

Russel also knows a fantastic tuner.   

My plans for tune is power house dyno in Mo

Joe is top notch.   


I was kidding about Russel because he tuned it. He's very very good.

[Johnwesley]

Missed that one 

[Coff 06]

Here is a little more spirited build. It's all about what you want. Pipe is an important part of the equation too. this build with a fatcat would have a much better torque curve.
https://harleytechtalk.com/htt/index.php/topic,97306.msg1286027.html#msg1286027

This is my bike. I changed to a Python 2-1 similar to a pro pipe. The torque is all in before 2500 and it's a blast to ride now.it will spin the tire into 3rd gear now.In no way would it do that with the Python 2-2 that was on it when it was tuned.Had plenty of power but no low end torque like now.Don't have a new Dyno sheet yet.               Coff 06

[Johnwesley]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

This brings up a good question I haven't thought on a good Hp Tq curve that might look good and not be responsive. That would suck.

[tommy g]

I had the 625 in my 98" 10.8. Ran great. Where it shined was at part throttle. 20% pic is comparing to another 98 build.

A HUGE difference in that throttle position.

[harpwrench]

I'd try HP103

[Johnwesley]

I've been studying specs on all the cams and it appears that the tman 590 and the woods 8 are very similar with the exception of a little more exhaust duration. Even the Same lobe centers and lift. So could you say that they respond similar with the tman just being quieter?

All of these cams apear close to each other

[Ohio HD]

When looking at cam specs you only get to see the intended actions of the valve opening and closing. When you can't see is lobe shape that can also effect how a cam can add to how well it will work in an application.

Here's how I decide, once narrowed down to a couple cams, looking at similar builds with dyno sheets to review. For a street bike I would lean in the direction of what RPM range you honestly will be riding in. ALMOST everyone rides between 3,000 to 5,000 RPM on the open road. In town they ride anywhere from 2,000 to 4,000 RPM. 98% of the time these are the RPM's you're in. So pick what looks to give what you want in those RPM's.

If you really must have the most power at top end and not concerned with anything else, that makes the selection easier. But the 98% of people are unhappy with that selection. It's a common thing called "over cammed" where the bike may not perform where you really ride.

Secondly but not by any means last, if you're using Joe Lyons to tune the bike. Talk to him. He has first hand experience with many cams in similar sized motors and exhaust combinations. I would trust Joe to steer me in the right direction.