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Discussion Starter #1
Does anyone have a lot of miles on a twin cam stock 88 cylinder bored to 98? Like 10K plus miles in the mountains, doing 85 on the plains, and the heat of the desert. How about the hour plus ride through downtown Sturgis on a hot afternoon? I'm reading 98's are OK and work fine but how durable is it, how long would it be expected to last?

Dave
 

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Fastest Chkn N the South!
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(By your wording I assume you meant boring the stock cylinders) I recently asked this question here. I found out that there really aren't many folks who post here that have these setups yet. I've got only 200 miles on mine so I'll keep you posted. What I can tell you so far is that I don't think there will be any heat issues when set up correctly. After 100 miles, the last 50 of which were at 75-80 mph yesterday, the oil temp never got over 225. When it idled it actually cooled down quickly. It was only around 80-85 degrees yesterday though.
 

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Cruisin' on down the road
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I have around 7000 miles on my GMR 98" build (one month since the build). I don't have a temp gauge to tell you what the oil is at, but I can tell you that it feels just as hot as it was with the Dewey Pro-street 95" and with that I was fequently in the 240 - 250ºF range. I'm having a bit of an oil issue (1 qt every 1000 - 1500 miles) so I'll keep any more comments to a minimum until that is resolved. So, it won't be until the Spring that I'll be able to measure the temps.
 

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Are you speaking about a mild build under 10:1? a build like that souldn't have any problems with a proper installation and a good tune. Any time you go to a high comp with high lift cams and better than double the horsepower, you are looking at a potential problem - an engine that won't go 100k. That is true of all builds.
 

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<<I have around 7000 miles on my GMR 98" build (one month since the build). >>

7K in one month...wow...so your "cruisin1966" handle really is your miles riden per week, eh? LOL
 

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ejk_dyna said:
<<I have around 7000 miles on my GMR 98" build (one month since the build). >>

7K in one month...wow...so your "cruisin1966" handle really is your miles riden per week, eh? LOL
Just got back from a 6800 mile trip, and had about 600-700 on the build before leaving. Picked up the bike from the shop on Sept. 11th and arrived home from my trip on the 30th. So, about 7500 miles in that time.
 

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Discussion Starter #7
route66paul said:
Are you speaking about a mild build under 10:1? a build like that souldn't have any problems with a proper installation and a good tune. Any time you go to a high comp with high lift cams and better than double the horsepower, you are looking at a potential problem - an engine that won't go 100k. That is true of all builds.
This would be fairly mild with 9.7:1 and Andrews 37G cams. I would settle for 100K, would certainly be playing with something else by then.

Thanks,
Dave​
 

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Wow!! I'll be bored by the time I hit 50K and more than ready to go for more...
 

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Cruisin1966 said:
I have around 7000 miles on my GMR 98" build (one month since the build). I don't have a temp gauge to tell you what the oil is at, but I can tell you that it feels just as hot as it was with the Dewey Pro-street 95" and with that I was fequently in the 240 - 250ºF range. I'm having a bit of an oil issue (1 qt every 1000 - 1500 miles) so I'll keep any more comments to a minimum until that is resolved. So, it won't be until the Spring that I'll be able to measure the temps.
Do a leakdown test.
 

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pa-glazier said:
Do a leakdown test.
As well as cold and hot compression tests.
 

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DaveS said:
This would be fairly mild with 9.7:1 and Andrews 37G cams. I would settle for 100K, would certainly be playing with something else by then.

Thanks,
Dave​
If you really want to be sure, have a pro put it together. someone who has all of the tools and who checks everything. Using the correct pistons and sizing the bore to the piston, using the good gaskets, checking all of you tolerences - this stuff is important. if you just put an engine together with whatever parts, or if you pay attention to the details, proper balancing on most engines, proper quench, a good port job - all these things make for a better build. One that will run faster, cooler, longer.
 

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We are told all these 98s are around for awhile. But I haven't seen any serious mileage #s. That goes for all the various types. Myself and Geezer had 20k on RP. Which to me is not to prove anything, and GG is down right now anyways.

I am sure there are people with more miles then us. They kits are sold out in the real world too.

But myself, I would like to see some bikes with some real miles on the cylinders.
 

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Cruisin1966 said:
I have around 7000 miles on my GMR 98" build (one month since the build). I'm having a bit of an oil issue (1 qt every 1000 - 1500 miles) so I'll keep any more comments to a minimum until that is resolved.
I assume that your build is with the stock cyls bored to 98", correct? Do you know if your oil usage has anything to do with using the stock cyls?
 

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ndmp40 said:
I assume that your build is with the stock cyls bored to 98", correct? Do you know if your oil usage has anything to do with using the stock cyls?
Yes, stock cylinders bored out to 98".

I don't think it has anything to do with the cylinders themselves. Without tearing it apart, speculation is all that there is for the reason for the consumption.

Could be a "tweaked" piston oil ring. Could be any number of things.
 

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It really comes down to the machine work, the checking of it and the assembly. If the important things are checked out and installed correctly, the engine should last. If you try to go cut rate, you might get lucky and then again, you might not.

The farther from stock that you go, the bigger the chance of catastophic occurances. There is a reason that the racers use aftermarket cases that have been strengthened and heavy duty evreything for thier engines. A stock TC engine that is built for double the original horsepower is about as far as I would go. If you want more, go with Jims or S&S.
 

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food for thought

perhaps the question here is are there any folks out there running the axtells bored 3.932 or 3.937?

Axtell's calling them 97" and 3.938 is called 98"...
.001 wont make any difference at all with the durability factor were all wondering about...
 

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The Axtells aren't bored stock jugs. They aftermarket jugs with more meat and thicker cooling fins.
 

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oh1deuce said:
The Axtells aren't bored stock jugs. They aftermarket jugs with more meat and thicker cooling fins.
But still stock diameter cases. Does that mean anything dunno. But good to mention, and time will tell how important.
 

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I think the meat of the sleeves in the Axtells are thicker above the cases where the fins are, and at the base of the jugs where they engrave "Axtell" in them. Which is obviously still above the cases. They must machine down the part that goes in the cases.

I guess I was just saying it's not apples to apples with stock jugs.
 

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Liner Thickness

When I get a chance, I'm going to bore the iron liner through to the aluminum, on a random cylinder we have here,record the dimensions, and then post them.
I do believe that the OEM cylinder is fine for a 3.9375 bore.
Scott
 
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