Topic: lowering a cb750 i know its been covered

[754]

 He never said WHAT he is using it for, good job we have claryvoyants to tell us..
 I have run around 1.5 under on the street a lot, and then slide them up to around 3 under for the strip. I got high pipes and cut off my sidestand mount so I have gobs of clearance.

 Cutting 2 inches off probably translates to 1.7 ish drop depending on the rake..  My bike is going slightly uphill, back is lowered more than front, so it ends up slightly raked..

[Retro Rocket]

And you are the only one saying it's about drag racing, Just an educated guess , seeings though he can't afford to buy shorter tubes one would think he definitely isn't racing.  Actually Frank, i have no idea why you keep comparing choppers and lowered bikes and rigid's to regular street bikes, {you do it a lot} they all handle like sh1t on the road compared to a "normal" bike, there is absolutely no comparison. I don't care what anyone says, lowering your 750 is NOT a performance modification, period.

[754]

 You are missing the point, streetracers, or diggers may not be common where you hang out, but that does not mean they do not exist.. In fact there are still lots of them, look at all the longarm Busa parts out there..
 Where we live, thay can now take your bike away for wheelying.. .. not so much problem on a slammed ride..  At least we can still piss araound with out being ticket bait 24/7...
 I havent ridden my slammed one a few years, but sure would like to be riding it sometimes..

[Eddie]

I would think lowering the center of gravity while maintaining decent ground clearence for turns would be a performance mod. I know my bike handles better being lowered 2"ish.. #1 by streatching the swing arm and #2 pushing up the tubes..

[Retro Rocket]

I would think lowering the center of gravity while maintaining decent ground clearence for turns would be a performance mod. I know my bike handles better being lowered 2"ish.. #1 by streatching the swing arm and #2 pushing up the tubes..

That is a complete contradiction, lowering the bike takes away ground clearance therefore reducing performance. A lower center of gravity is great but there's no way of doing that on an old Honda 4 without limiting its overall performance, you are better off reducing unsprung weight,  its quite possible to scrape the alternator cover on these bikes at standard height, not to mention the footpegs, including the bracket, center stand and pipes. Lengthening the swingarm and reducing trail at the front is NOT a performance mod either.  I still get surprised at what some people on this forum think is a "performance mod", you ride your bike in the twisties, i'll ride mine and you will soon find out the short comings of what you just said and your "mods"...

Frank, mate you don't get it either, the bikes you refer to handle like sh1t, the mods you talk about are NOT PERFORMANCE orientated mods, on the strip maybe but definitely not on the street {remember the street has corners }. The reason we don't have those ridiculous Busa's with 3 foot swingarms here is because they are dangerous when compared to the original bike and deemed "unroadworthy, i completely agree besides i don't know anyone that would be stupid enough to do it..... I can't believe we are discussing this in the "performance" section of the forum..... And Frank, i know you like "altered bikes" i do as well, its just your interpretation that leaves a lot to be desired..

[Eddie]

not everybody on here wants to do "twisties". My bikes steering is still very responsive, can still do the goofy figure 8 that the state of Illinois requires to get your license. and if you ever get a chance to find a smooth road in Ill.  I doubt I'll ever lean it over far enough to scrape the alt cover or center stand... lots of straight line riding...hence a streched bike is more stable....so it is a performance mod..   look at the pic and tell me it wont handle and I dont have enough ground clearance.

[754]

 iIs not my interpretation, it what is seen on the streets here..
 Some of us could give two figs about EVER cornering as hard as the bike is capable of.. something you dont seem to grasp..
  You ever notice how some folks like their bike to look like a race replica.. like an Eddie Lawson bike.. or a Repsol honda.. or a CR 750 Honda..

 Well its the same on dragbikes and hot streetbikes.. Some folks happen to like a bike to look like Russ Jr's current racer.. but hey dont take my word for it.. ask him... Have you EVER been over here or checked out the bike mags from here...?  ?  ?     ?   ?

[Retro Rocket]

iIs not my interpretation, it what is seen on the streets here..
 Some of us could give two figs about EVER cornering as hard as the bike is capable of.. something you dont seem to grasp..
  You ever notice how some folks like their bike to look like a race replica.. like an Eddie Lawson bike.. or a Repsol honda.. or a CR 750 Honda..

 Well its the same on dragbikes and hot streetbikes.. Some folks happen to like a bike to look like Russ Jr's current racer.. but hey dont take my word for it.. ask him... Have you EVER been over here or checked out the bike mags from here...?  ?  ?     ?   ?

I meant your interpretation of what you consider a "performance" mod for the street, i understand everything else. I have had lots of performance street bikes and thats exactly what they were, better than stock in both HP and handling...   You are actually arguing for me, if you make a "street" bike worse at cornering on the street then its not a "performance mod".  Its not about riding around corners at a million MPH either, all roads have corners.    I think some have the wrong interpretation of Performance, sure as hell sounds like it...

not everybody on here wants to do "twisties". My bikes steering is still very responsive, can still do the goofy figure 8 that the state of Illinois requires to get your license. and if you ever get a chance to find a smooth road in Ill.  I doubt I'll ever lean it over far enough to scrape the alt cover or center stand... lots of straight line riding...hence a streched bike is more stable....so it is a performance mod..   look at the pic and tell me it wont handle and I dont have enough ground clearance.

A stretched bike may be more stable in a straight line but its not a Performance mod if it makes it worse at anything required for the street, i am not saying you ride like an old lady but if you have trouble scraping a center stand on an old stock height Honda then you probably will never ride hard enough or well enough to know how these bikes really handle anyway.  If you lengthen the rear it will help with straight line stability,  drop down the forks you are reducing trail at the front, reducing trail makes the front more nervous so you now have a bike that the rear wants to go straight and the front wants to go left and right and will occasionally induce a head shake {tank slapper}, if you think i'm wrong then go read up on frame geometry, even 754 {Frank} will tell you that long bikes, choppers, diggers and the like also have longer trail numbers due to rake changes, {more rake, this adds stability in a straight line by adding trail which aids stability}. I don't mind discussing "performance" mods with anyone but it surely helps if you know what you are talking about.... Also after owning 40 odd bikes and 20+ old Honda's I have a fair idea how well they handle and how much ground clearance they have, lowering the bike then extending the rear is NOT a performance mod for the street, its just a modification.

[dragracer]

How did this sway away from the original question about a method of lowering frontend?? Can't see how any of this is helping the poster get the results he's asking about to begin with- sorry guys but i think this discussion is off topic now.

[dragracer]

By the way, i used a 3" pvc spacer at the foot of my tubes to lower my F model. Yeah, i'm cheap but i had just spent a ton of $$ building the bike from scratch. I made a huge mistake and cut the damn spring. Should have left it stock length as i needed to stiffen up my frontend for dragracing. Will be putting stock springs in when i replace the fork seals this time.

[754]

 Very stiff fork really helps reaction times, I have found..

[Greg H]

Back in the day I ran my F based drag bike/sprinter with 3in spacers up front with the stock spring length to stiffen up the front end anwith the rear end lowered sufficiently to lower the rear end and  increase the trail slightly . This helped when launching and proved to work at high speeds as well( when fitted with my 970 motor for top speed events )  when the bike also ran a 2ins over swing arm for extra stability as well . For cornering etc on the street we usually used to have to raise bikes to increase ground clearance and play around with the forks in the yokes to quicken up the steering . I also used to do a bit of circuit racing on production based bikes as well as plenty riding on the street  so I know from experience that the set up required for hard launches and straightline stability is not compatable with the quick steering/ground clearance which you would usually need on the street .However ,I suppose if you're after a particular look to the bike, there may be some sort of half way house in set up which would require plenty of trial and error to get right and most importantly ,safe .

[Really?]

During the rally, I was really surprised at how much of the tire I was able to use in the twisties of the hill country. I will say that I really had to work the bike a lot to keep up with the 550's and still feel that they kicked my butt. The only saving grace were the straight parts of the road where I could accelerate. It was a really good workout.

At normal height, I bet I could of been right there with them. Even at my age.

[Really?]

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[Really?]

Sorry for the same pic twice.

[romerider153]

And you are the only one saying it's about drag racing, Just an educated guess , seeings though he can't afford to buy shorter tubes one would think he definitely isn't racing. 

It has absolutly nothing to do with not being able to afford it i have access to a machine shop for next to nothing through my work so im just considering other options. i just like to spend my money wisely the bike is 100% custom nearly every part is replacced and im in the process of finishing up my turbo setup so im not some broke ass trying to hack together a bike

[romerider153]

thanks to everyone else who had some good info and personal experience to help with my decision .

[Retro Rocket]

And you are the only one saying it's about drag racing, Just an educated guess , seeings though he can't afford to buy shorter tubes one would think he definitely isn't racing. 

It has absolutly nothing to do with not being able to afford it i have access to a machine shop for next to nothing through my work so im just considering other options. i just like to spend my money wisely the bike is 100% custom nearly every part is replacced and im in the process of finishing up my turbo setup so im not some broke ass trying to hack together a bike

Well that wasn't my point, my point was that it is a street bike. You assumed the rest....   {i was assuming as well, that it was a street bike...}  Sometimes it helps to read everything...

[Eddie]

 
 " Sometimes it helps to read everything..."

and sometimes it best to say nothing at all..

[romerider153]

^ agreed its not a strict drag bike your right but it definitely is a more straight line oriented bike I'm not planing on drag knees around turns i just want a bike that i built that i enjoy, that has the stance and look that i want.  The not wanting to pay for tubes has nothing to do with not being able to afford it that's the only comment i thought was unnecessary you are obviously a if you can afford just buy it kind of guy but I'm a if i can build it myself why pay for it kind of guy as I'm sure many others on this forum are.

[Retro Rocket]

 " Sometimes it helps to read everything..."

and sometimes it best to say nothing at all..

Practice what you preach...

Also go look up what a FORUM is....

^ agreed its not a strict drag bike your right but it definitely is a more straight line oriented bike I'm not planing on drag knees around turns i just want a bike that i built that i enjoy, that has the stance and look that i want.  The not wanting to pay for tubes has nothing to do with not being able to afford it that's the only comment i thought was unnecessary you are obviously a if you can afford just buy it kind of guy but I'm a if i can build it myself why pay for it kind of guy as I'm sure many others on this forum are.

It wasn't meant to be derogatory at all, somewhere you said that "i really dont want to pay for shorter tubes."   You are in the US and your economy is crap so i thought you may have had better things to spend your hard earned on... No offense intended....