Motor work...88 vs 95

well. how much do you want to spend??? boy thats so wide open.... - ok a few random thoughts:

there is a great site that shows lots of dyno charts for various combinations - latus motors in oregon. check it out.

i think the obvious goal is the most torque you can get below 4000 rpm above 4000 - who cares, seriously - and of course - durability

stone stock will last the longest - at least in theory - but i had the cam chains crap on my 88" fixed on warranty and then i traded it for a 96" [note that there are variations on "stone stock" 103's ARE stone stock police engines..... so its never completely simple]

88" with a gear drive torque cam, SE 4" mufflers 103 type air cleaner - and sert to tune [sert is REALLY better - but power commander has more guys who can get ok numbers]

the largest cubes you can afford tuned for torque rather than peak HP - a cam like a SE 255 - stock exhaust head pipes - SE 4" mufflers or v&h classic round - and a se air cleaner - or the se 103 kit air cleaner. [the se 103 crank that comes in the "kit" is superior to the current 96" crank according to some]

88, 96" or 103" have the best durability biggest torque - parade fan keeps it cool - 255 cam gives near the best possible below 4k power. [stock sizes are: 88/stock cam, 95/203cam [early police bikes], 103/203 cam [later police bikes], 103/255 cam [current police bikes], 110/255 cam [current cvo bikes] - there are heat issues with the 110's but that kit wont go on a 88 simply . gear drive cams are more durable by far - do that regardless.

just be certain to not go for the high HP numbers - you will be bummed - low end torque and high end hp have a certain amount of compromise needed. two into one exhaust - true duals high end cams are all for max hp at 5000 plus rpm - you will have to pass trucks in 3rd.

if i had kept my 2000 - i would have done: 103, using all the provided harley parts, air cleaner everything - except: s&s gear drive cams, sert for dyno tune, port the heads. it already had the parade fan. but after the cam chain blow up i decided to trade rather than take the risk. [ya i was chicken]

later

to

Thanks Timo,
I did talk to him about the tuning as well, he does all his own headwork and dyno tuning in house. He said the sert can be tuned a little more precise than a pc, but for what I'm doing he could make the pc perform just as well. This guy has been building motors for over 10+ years and has turned out some pretty amazing work. Price is another major factor as well, I wish I had an unlimited budget but not that case and that's been one thing we've been working on as well. Trying to keep it under 3 grand, closer to 2,500 if possible. Getting the most bang for the buck. I had the HD 95 Stage II Big bore on my 02 RK and liked it, but for the money I can get a lot more out of my motor than a "out of the box" kit from Harley. That is a good reminder though, I need low and mid range power, not top end power. I won't be pushing this motor over 4k much at all.

are you going to replace the pistons? are the bores worn out? need new rings?

if so - id still go as big a cubes as you can get - remember "there is no substitute for cubic inches"

if not - then focus on gear drive torque cam & tune

if the rod bearings are suspect - then a 4 3/8 stroke flywheel set.

under 4k rpm the cam and cubes make more difference than head, porting, exhaust. head and porting are always good - but ive seen 110 se new take off heads for 400 on ebay. [note se 110 cylinders are suspect - the heads are fine]

on my current bike [stock 96"] i can run 80 on the cruise control bike and sidecar fully loaded - essentially its a stroked 88.... ill change the cam to a 255 before id go larger bore.

later

to

I have a 95" in my 02 RK. Once you open the motor, its pretty cheap to get a set of pistons, maybe $3-400 tops. Cheapest torque you'll ever get, imho. I did the 95 with 10k miles, added gear driven cams at 45k, after the 3rd set of the stock spring drivin lifers failed.Last time we tuned in on the dyno, it had 110 lbs torqe, 100 hp. The engine now has just under 70k, still runs like new. It has lots of torque, certainly more than stock. I plan to add a sidecar to it this summer. Personally, I don't think a stock 88 would be much fun with a sidecar, particularly at any speed. The sidecar really adds a lot of drag. When my RK was stock, it had issues climbing mountains (without downshifting) with me and Connie and full luggage, much less a sidecar.

Originally written by gregbenner on 1/26/2008 4:06 PM

I have a 95" in my 02 RK. Once you open the motor, its pretty cheap to get a set of pistons, maybe $3-400 tops. Cheapest torque you'll ever get, imho. I did the 95 with 10k miles, added gear driven cams at 45k, after the 3rd set of the stock spring drivin lifers failed.Last time we tuned in on the dyno, it had 110 lbs torqe, 100 hp. The engine now has just under 70k, still runs like new. It has lots of torque, certainly more than stock. I plan to add a sidecar to it this summer. Personally, I don't think a stock 88 would be much fun with a sidecar, particularly at any speed. The sidecar really adds a lot of drag. When my RK was stock, it had issues climbing mountains (without downshifting) with me and Connie and full luggage, much less a sidecar.

I run my stock 88" bike with a sidecar. The only change so far has been to change the gearing to 3.37:1 with a new motor sprocket and a clutch basket. In my opinion, a change of gearing ($300 for parts) is a better choice than cams and fuel changes.

The thing about making changes to a Harley engine is that typically it will raise the revolutions higher to get to the higher torque. I have no issue with anyone who wants more power but if you have a loss of low-speed torque (below 2,000 rpm) with different cams and more heat to boot, then it may not be good for a sidecar. Also, if you raise compression, you need premium fuel all of the time. I can run 87 or 89 octane with no trouble on 8.9:1 compression. Yes, yes, I can afford premium.....don't need it.)

Yes, sidecars do create more drag....of course they do, they are after all...well, they're...ahhh.....sidecars. I don't know if you've ever ridden one much, forgive me if you have. If not, you might want to think about that before you buy one. You won't be keeping up with the other group riders anymore.

As to fun, We have plenty of fun with our stock 88" and Harley sidecar. 85 mph is fast enough for me. LOL

Actually, if you use the right cams, you can get more low end torque. I dynoed mine before and after, my goal was torque, not hp. Huge increase in low end torque, well over 100 lbs, at the lowest rpm range on the chart (i.e. a flat line). Gearing is also a great idea, will probably do that to my RK this summer when i add the sidecar. Beleive me, there is no substitute for cubic inches, when it comes to torque.

Originally written by gregbenner on 1/29/2008 8:31 PM

Actually, if you use the right cams, you can get more low end torque. I dynoed mine before and after, my goal was torque, not hp. Huge increase in low end torque, well over 100 lbs, at the lowest rpm range on the chart (i.e. a flat line). Gearing is also a great idea, will probably do that to my RK this summer when i add the sidecar. Beleive me, there is no substitute for cubic inches, when it comes to torque.

Show me the dyno runs that have this increase in torque at 1,500 rpm. Don't forget the cost either: air cleaner, mufflers, SERT or TIFO, fooliing around time and dyno time....I've been there and done that with Harleys. For my sidecar work, I leave the engine alone.

Also, the cam drives in the Twin Cam are really weak. What, you say, you don't have gear drives? Nope, I'm not sure if the crank is straight enough and I don't care to spend another $600 bucks when I can go riding.

I do all of my own work, I even have all of the tools for the cam work and tensioner maintenance. I stay away from the dealers when I can. So far, I've changed the inner bearings to Torringtons and added a Baisley/Latus oil pressure spring and adjustable pushrods. That's it, though. Got to keep going and riding and let the other guys screw around with their bike engines. That stuff makes for good conversation at bars and barbecues but it's a waste of time for sidecar riding. BTDT as I said.

Oh, gosh, I forgot the EPA and CARB. They are coming to get us. Here in California we have not yet had to undergo hot testing like the cars. That's coming. When they do that on a car, they also do a oomplete configuration test. That is, they look at mufflers, catalytic converters, air cleaners, even the fuel cap for OEM configuration. I had to buy a new stock fuel cap for my Dodge truck a while back before they would test it. It wouldn't hold vacuum. If they start that on bikes, all of the mods have to come out, I said, all of the mods have to come out!!!! In California, this is only a matter of time.

Lastly, if you look around a the world of sidecarring, most are running stock engines. There are countless numbers of BMW's, Dnepr's, Urals, Triumphs, BSA's and you name it brands that are making it in sidecarring with less than 60 hp. They're having a lot of fun, too. Instead of working on their engines all the time, they're out riding.

Don't let me stop you from spending money, though. LOL

staying legal and reliable is important

page 536 of the 07 screamin eagle book - LEGAL 103 kit on 88" bike - 80 ft lb at 2k, 90+ ft lb, thats 15lb more at 4k - drops from there. hp is 10 more at 2k and 15 more at 4k its the stock configuration of a late 103 police bike.

the LEGAL 95" kit has less improvement at 2k - about the same at 4k

on the same page is the 103 with 255 legal kit - 90 ft lb at 2k - and then the 110 legal kit - really big torque at 2k.

the harley legal kits are just exactly right for sidecar use - but im not going to do any of them till there is some reason to open the engine. stone stock is still best.

just remember - there are several options for legal stone stock.

to

I do have gear drivin cams, the stock lifters gave me problrms.I do think it depends a lot on driving habits, etc. If you think a stock 88 has more power than you need(without a sidecar). you would probably be fine. i thought the stock 88 was underpowered from the getgo. After we got the 95, i rode to Michigan with afriend on his 88.He was sole, i had Connie. He was fine untill we got in the mountains in colorado. He just couldn't go very fast. I cracked the throttle and rode away. he had always argued the 88 was fine, untill then.When Connie and I went to Alaska this summer on the Goldwing, we met a couple on a new Harley Ultra with the 96" engine. he was pulling a trailer, which isnt nearly as big a drag as a sidecar, he commented he wished he had a WIng, because he didn't have enough power, particularly on the open road, and in the mountains. He was thinking of getting a 110" motor built. All that said, an 88 will get the job done, just a little slower.If money is an issue, I certainly understand why someone would leave it alone.

The only change so far has been to change the gearing to 3.37:1 with a new motor sprocket and a clutch basket.

How does the gearing affect you on the highway? Do you ever have to ride on the interstates? I am curious because my RK (no sidecar yet) seems like it needs another gear as is, and gearing it lower would axacerbate the problem(maybe). Living in the LA area, makes it difficult to completely avoid the interstae.Did you need to by a new belt as well?thx greg

Originally written by gregbenner on 1/31/2008 12:40 AM

The only change so far has been to change the gearing to 3.37:1 with a new motor sprocket and a clutch basket.

How does the gearing affect you on the highway? Do you ever have to ride on the interstates? I am curious because my RK (no sidecar yet) seems like it needs another gear as is, and gearing it lower would axacerbate the problem(maybe). Living in the LA area, makes it difficult to completely avoid the interstae.Did you need to by a new belt as well?thx greg

It has to do with your frame of reference. AFAIK, most of the 88's had the 3.15:1 gearing, which is too high for a stock 88" machine pulling double with a trailer going up hills, etc. Harley did this for the EPA, mainly.

On the other hand, virtually all of the Evolutions were fitted with the 3.37:1 gears. This represents tens of millions of road miles and it proved to be a good, all around gear, easily permitting 100 mph, which is all that most HD's do in any case, LOL.

I've always considered 3.37:1 to be the perfect gear. the difference between 3.37:1 and 3.15:1 is only about 500 rpm at 65 mph. A small but important difference since it will pull a sidecar with ease.

With all due respect, you need to decide the purpose for your bike - will it be a solo bike or a sidecar tug? If you have a lot of engine mods, you may lose some low-speed pulling power. If your thought is to remove the sidecar at a moment's notice, first that's a lot of work. Also, with later HD's you really should have the dealer toggle the sidecar Bank Angle Mod unit (88115-03) to sidecar use. This converts the Bank Angle Sensor to sidecar configuration so that it won't kill the engine in a hard turn with your sidecar. I've had this done and it's fine for sidecar use but if you remove the sidecar, you will be at risk since the engine won't kill if the bike falls over, only if it rolls upside down....you could have the dealer change it each time you go solo but they usually get a half-hour....nice, huh? LOL.

In any case, the gearing makes the bike really go to work with the sidecar. Remember, Harley has had sidecars for close to 100 years now and lower gearing was the key. This becomes clearer when you consider that the 1946 HD FL that I had when I was a kid only had about 45 hp! Those often pulled sidecars. Go figure! LOL

As to to how the change is done: With the 3.15 geared Twin Cam FL bikes, (up to 2006 FL's) the change from 3.15:1 to 3.37:1 requires changing the motor sprocket from 25 teeth to 24 and the clutch basket from 36 to 37. The parts are stock and the same front chain is used.

When HD went to 6 speeds with the newer primary (2006 Dynas, 2007 and later FL's and others, IIRC), there are no stock parts available as of yet. I've heard that there may be some in the aftermarket...you'd have to check. In any case, the gearing with the six speed bikes is way, way, way, too high, even for a solo, something like 2.97 or so!. (The EPA again!) I guess you might have to change rear sprockets and the belt but that's an incredible amount of work and would change your speedometer reading to run faster. Bad! My bike is a 2004 and the change took about three hours with the two parts for around $300 discounted on the internet. I only had to open the primary case.

Since I have a bum left hip, I will leave the sidecar on and enjoy it. Riding is riding anymore.

Regards. gnm109

Gnm109, thx for the reply. I actually have a new Dyna with the 6 speed, top gear is very nice at highway speeds, much better than the 5th gear in my RK. I do plan to leave the sidecar on the RK permanently, the question is that with the stock gearing, the RK revs a little high on the interstate (75mph+). Even at 70 for long distances, i find myself contantly trying to up shift to a gear i dont have. Probably why the Motorcompany addded the 6th gear. With lower gearing, I suspect the cruising speed is limited to 65 or so, which likely would be OK, since i would use the Goldwing for any really long trips. I appreciate the info on the parts needed. I will probably wait to see how/where I actually ride it after I get it done. For local use, the lower gearing sounds pretty cool.

A couple more questions. I had thought this might be a good time to replace the clutch on my RK. Its the original one with 70k miles, and although it seems fine, it must be getting pretty worn. Same with regard to the alternator. Although i don't know for sure, i never thought the stock RK alternator had a lot of extra capacity. Again.maybe time to upgrade? Any thoughts?thx, greg

Originally written by gregbenner on 1/31/2008 2:43 PM

A couple more questions. I had thought this might be a good time to replace the clutch on my RK. Its the original one with 70k miles, and although it seems fine, it must be getting pretty worn. Same with regard to the alternator. Although i don't know for sure, i never thought the stock RK alternator had a lot of extra capacity. Again.maybe time to upgrade? Any thoughts?thx, greg

Your clutch could be examined for wear. Unless you've had trouble with it, there's really no point. They sometimes begin to slip or stick when the clutch basket bars get notches in them from long use. The plates seldom wear much if the primary oil is changed periodically. This can be seen when you pull it apart for a look. That would be a good time to change the gearing.

I assume that your RK is a five speeder. As I said, there are no factory re-gearing parts for the six speeders and these probably won't be forthcoming from the MoCo anytime soon since the OEM gearing has to do with fleet emissions vis-a-vis the EPA and CARB.

With regard to the alternator, a visit to your parts book or to the dealer will tell you if there is something better on the market. Some were 40 amp and the Ultra was 45 until the six speed bikes came out with the larger engine...those are, I think 50 amps but may not interchange since they are three-phase. If your alternator is still working, I would leave it since there is a rather high failure rate on those and, if yours works, it means that you have a good one. There are better ones for five-speeders on the market, Compufire for one, but they are pricey and I tend to stick with OEM parts.

Happy Trailsw!