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I've seen this asked about multiple different bikes, but can't find anything specific to the vulcan frame/neck. What kind of front end could i get for my 97 vn750 that would allow me to put a fatter front tire on? I'd like it to be as close to the rear tire size as possible. I'm not sure if this is possible without replacing the neck of the frame, but I thought I'd ask!!!
 

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If only it had 6th gear..
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Curious .... why would you want to have your front tire as wide as the rear? I believe the bike might handle like a toad since its designed for a pizza cutter up front but I may be wrong . I think there's a thread on here with pics of a rear tire mounted on a vn's front, end (not mounted on the bike tho). Ill see if I can find it and update...
 

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I could swear someone put a front end off a larger bike on the 750 without changing the neck, but not 100% sure what front end they used.

Perhaps someone can jog my memory on this and help you out also?

JD might know....Try sending him a PM:
http://www.vn750.com/forum/member.php?u=257
 

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I have some information on this... Check out my scribd link and look for ocr tube sizes... there are a lot of different bikes that share the same neck bearings as our vn750... the vn1500 BUBF is an almost bolt on mod... IIRC a spacer needsto be made for the top tripple tree... other than that it bolts on.
 

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Discussion Starter #5
I have some information on this... Check out my scribd link and look for ocr tube sizes... there are a lot of different bikes that share the same neck bearings as our vn750... the vn1500 BUBF is an almost bolt on mod... IIRC a spacer needsto be made for the top tripple tree... other than that it bolts on.

I'm guessing it's in the "DIY Manual" file?
 

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If only it had 6th gear..
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I'll ask again cuz I'm definitely interested. What are the advantages on this style bike to have a fatty up front? I do think it would look cool but are there other advantages like ride comfort, gas mileage ir whatever?
 

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I'll ask again cuz I'm definitely interested. What are the advantages on this style bike to have a fatty up front? I do think it would look cool but are there other advantages like ride comfort, gas mileage ir whatever?
The only real advantage to having a bigger ,i.e. wider tire is having more rubber on the road. Take a look at most sport bikes... they usually have pretty wide tires... Or at least ones closer in width to the rear.

But these bikes were engineered for this. Putting a radically wider tire on a cruiser seems kinda silly. It will increase gas consumption, make an already slow steering bike harder to steer, increase unsprung weight, and in my opinion... Just look weird.

The only reason I can see for getting a huge tire up front is if you are adding a sidecar. The stock wheel will take a 110 tire, which I think is a good thing. But going as wide as the rear? Not going to be an improvement in anything other than the increase in traction...but can cause other chasis/suspension problems.
 

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If only it had 6th gear..
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Thanks Km. Kinda what I was thinking, especially with the gas mileage suffering because of the added ground contact/friction etc. Personally I like the onion ring up front and donut in the back with this style. I think that's why I like the Sportster look more than the bigger HD's. Small fenders etc. Never thought about the sportbikes having widers up front but that def makes sense. Your FJR has similar (or maybe even the same size?) on the f & r. Bet you get serious handling on it.
 

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The FJR has a 120/70 front and a 180/70 rear. They both are 17" rims. And Z rated tires.

When I said sport bike fronts were wider, I did not mean they were the same, just that you don't see really wide rears with tall skinny fronts like you do on cruiser bikes or custom-choppers.

I do think there were a few race/sport bikes that had very simular width front/rears, (smaller displacement bikes I believe) but as all bikes are rear wheel drive, having a wider rear is usually the logical pick.

I still recommend the 110 tire up front for the Vulcan...
 

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Wide tires...

There IS an advantage to wide tires depending on where/how you mostly ride. For example : I live in farm and mountain country...many of the roads are in poor shape and even gravel. Almost all around here go for wider rims and tires. Adds to the "cushioning" effect that at times the forks wont produce, especially if slightly underinflated (10%).
After my accident with my SuperGlide (Showa forks bent like they were copper), I put a '53 wideglide front end on it. Triple tree bolted right up. And I added a new front tire (part of the old left with the Delta 88) and got one width narrower than rear. Had a 16" rim on rear, and a 19" Hallicrafters spool on front. What a dream that was to ride !...never shouldda sold it.
 

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If only it had 6th gear..
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Ya man, I do hate riding on crappy roads with this bike. So many to choose from in Taxachussetts and some o' dem pot holes hurt!
 

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I could swear someone put a front end off a larger bike on the 750 without changing the neck, but not 100% sure what front end they used.

Perhaps someone can jog my memory on this and help you out also?

JD might know....Try sending him a PM:
http://www.vn750.com/forum/member.php?u=257
Yep; a 1500A front end has been put on a 750, altho it ain't hit the street. The triple tree bearings and neck/steering head length are the same between the two. No advantage, tho, as far as larger tire size; the 750 and 1500A use the same size tire and wheel, front and rear.

(Got the message, Darien; had to split the reply into three sections.)

In my reply to Darien's PM, I said it'd make more sense to use the same front end, and hunt for a wider wheel that'd fit between the fork tubes. A wider wheel is prolly gonna be smaller diameter, tho; I haven't seen a stock 19" wheel that could carry a tire wider than a 110 safely. (Doesn't mean there ain't one out there; I just haven't seen one, and haven't researched it.) Problem might be brake disc and caliper diameter and spacing, and axle diameter. Axle diameter isn't that big a problem; differences can be made up with different bearings, matching bearing outer diameter to the hub, and inner diameter to the axle. Brakes might be a whole different story...

Jim
 

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BTW, I know a guy that put an 800 front end on a 1500A; again, no advantage to trying an 800 front end on a 750, as the tire size on a VN800A is 90/21, and is tube type. Same guy turbocharged an early 1500 Classic...

Jim
 

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Ummmm

Not 100% sure on the triple tree size, but I know for awhile the Harley Sportsters and Superglides used the same forks as the Vulcan has (Showa), but I believe some Harley triple trees were wider. This way would almost be a bolt-on (prolly using harley brakes tho due to mounts), then just adding axle spacers (might need to have em custom machined), and also using a Harley compat rim (I like spokes, dangit)...If ya got lucky (not in my personal exp) but may just need to swap the triple tree and add spacers...THAT would be a dream ! I'd do it meself...
Just a thought, bring yer triple tree to a Harley shop, and ask em if there's a wider available...avoid tellin em what its for though, lol...say its off a Sportster...*wink*...
I had Japanese forks on my original '72 Super...a 53 front end fit (paid $100, and then changed seals)....I wonder if most necks are compatible....just a matter of replacement then. And think...one could even go to 1" bars !!!!:)
 

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Also...

Some custom shops which own a FloJet machine, could make you a custom triple tree...would be big bucks though, and IMO not worth it...
 

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I might have moved it.. I am looking for it right now... you its still labeled OCR Tube sizes, and OCR Stem Sizes... they are not in the DIY manual
Found this OCR website slim:
http://www.ohiocaferacers.com/

Check Tech tips as I can`t link directly to it.
Coversion Charts for Fork Tube Sizes & Steering Stem Bearings
Standard Fork Tube Sizes
Stock Steering Stem Sizes
 
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