Stuffing a 1500 rear end in a 1200....


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CrystalPistol
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1997 GL1500SE Lehman Trike

Re: Stuffing a 1500 rear end in a 1200....

Post by CrystalPistol » Fri Jan 20, 2017 9:33 pm



RoadRogue wrote:
Nik27 wrote:Hey RoadRogue how the hell did you het that 195 tyre into a 1200 swingarm....... etc ...
I dont know what to tell you, other than I had to mount the wheel and final drive together and then slide the drive onto the driveshaft and swingarm. There is enough room for the tire on my 86 Interstate. 8-)
Good Thinking! :)

I admit, when I first saw this thread and your post I had my doubts about the sizing. I thought maybe it was due to a typo. So I blew the pic up, played with exposure, and it is definitely a General Altimax 195 55 R16 tire on a GL1500 wheel on a GL1200 bike.

I see that tire is just shy of $90 at Tire Rack if it's the General Altimax RT43 with a V speed rating. Nice looking tire!


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RoadRogue
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Re: Stuffing a 1500 rear end in a 1200....

Post by RoadRogue » Fri Jan 20, 2017 11:35 pm

Lol, no its not a typo. This is a good tire all around and seems to be very good in the rain. 8-)


Ride safe, Todd
Over night campers welcome

Nik27
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Re: Stuffing a 1500 rear end in a 1200....

Post by Nik27 » Sat Jan 21, 2017 6:06 am

Hey CP...maybe the swingarm on an 85 is not as wide as an 86-87. Mine is as wide as this tire!! I can possibly fit a 175 60 16 this is .5 inch wider than standard MT.

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Re: Stuffing a 1500 rear end in a 1200....

Post by Nik27 » Wed Jan 25, 2017 8:54 am

Hi again...RoadRogue, I have heard that tyres size is different once fitted to a rim and inflated so maybe that is the secret of your success!! I know it's winter and all but any chance of a measurement of your swinging arm width where the tire runs before I rush off and buy the wrong tyre??

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Rednaxs60
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Re: Stuffing a 1500 rear end in a 1200....

Post by Rednaxs60 » Wed Jan 25, 2017 11:05 am

RoadRogue wrote:
Rednaxs60 wrote:RoadRogue - did you modify the rim in order to fit the CT. Other forums mention moding the rim to have easier install of the CT. Have a CT on my 1800 and want to do the same to my 1200.

Cheers
I tried to mount a 15 CT to the stock 1200 rear wheel once, it would not seat the bead even at dangerous pressures so I abandoned the Idea of Darkside my a 1200 until I found this conversion to the 1500 final drive with its 16" wheel. I knew that the CT would seat the bead at less than 40psi as I had done it twice before. First with the Austone tire and then with this Altimax tire, both very good Darkside tires in my opinion. There was NO need to modify the stock 1500 rim.
As for any differences in the bead seat area between car tires and bike tires both tires are made of rubber and will flex and mold to any discrepancies in the shape of the rim when aired up.
Some may say I'm nuts for putting a CT on a bike and they may be right but I'm not so nuts that I would modify the seating area of the 1200 wheel to allow the 15" tire to mount on the 1200 wheel. You would have to turn the rim on a lathe to remove the correct amount and still retain the proper shape. Seems that 15" bike rims are bigger diameter than 15" car rims. Is it doable? Ya sure but not worth the money or the risk of the thinner material in the rim. Not saying it can't be done, I'm just not willing to do that when this was so easy really only took a couple of hours 8-)
Went to the bike show in Abbotsford, BC and Dunlop tires had a booth. Spoke to a fellow there and talked about the new E4 that is out and how Dunlop states you should be able to get 6 trips across the US before replacement. This fellow mentioned he thought it was only four trips, but his partner mentioned I was correct at 6. The salesman did not know his product, and when I mentioned having a CT on an 1800 he went through all the old rhetoric that is mentioned about having a CT on a bike.

Decided to talk to his partner who was more knowledgeable. She had no comments on the CT but mentioned that sh went to Wingding last year and spoke to people who had CTs on their GWs. She mentioned that the primary reason was for economy and mileage. She also mentioned that the Dunlop E3 were being phased out for the newer E4 next year.

Hopefully the MT industry will start to listen, otherwise CTs will still be a tire of choice for touring bikes such as the GW.

Cheers
"When you write the story of your life, don't let anyone else hold the pen"

Ernest

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RoadRogue
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Re: Stuffing a 1500 rear end in a 1200....

Post by RoadRogue » Wed Jan 25, 2017 1:36 pm

Nik27 wrote:Hi again...RoadRogue, I have heard that tyres size is different once fitted to a rim and inflated so maybe that is the secret of your success!! I know it's winter and all but any chance of a measurement of your swinging arm width where the tire runs before I rush off and buy the wrong tyre??

I will try to get through the snow to where the bike is hibernating today and see if I can get you a measurement, will post back here tonight 8-)
Ride safe, Todd
Over night campers welcome

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CrystalPistol
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Re: Stuffing a 1500 rear end in a 1200....

Post by CrystalPistol » Wed Jan 25, 2017 9:11 pm

RoadRogue wrote:
Nik27 wrote:Hi again...RoadRogue, I have heard that tyres size is different once fitted to a rim and inflated so maybe that is the secret of your success!! I know it's winter and all but any chance of a measurement of your swinging arm width where the tire runs before I rush off and buy the wrong tyre??
I will try to get through the snow to where the bike is hibernating today and see if I can get you a measurement, will post back here tonight 8-)

Ummmm .... while out there and all ...... would it be too much to ask for a measure of the General 195/55-16R tire itself in overall width ???

Thank You!

(I measured my MV85-15 Dunlop Elite II at 6-3/16" (6.1875) inches. Looks like 15/16" clear on left side but right side is only about 3/8" from drive shaft tube)
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RoadRogue
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Re: Stuffing a 1500 rear end in a 1200....

Post by RoadRogue » Wed Jan 25, 2017 10:25 pm

Ok ,I survived the trek through the snow to the back 40 where the 1200 is housed for hibernation. It was a tight squeeze to get underneath to take the measurements but I have the requested numbers for you.
Inflated tire 6-3/4", General Tire Altimax HP
Driveshaft clearance approx 1/4" (a pencil wont fit in between)
Brake side tire to swingarm 1/2"
Total swingarm width should be 7-1/2" this is a 86Interstate 1200.

There is absolutely NO signs of tire rub on the driveshaft tube whatsoever.

Any other questions ? Just ask! 8-)
Ride safe, Todd
Over night campers welcome

Nik27
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Re: Stuffing a 1500 rear end in a 1200....

Post by Nik27 » Thu Jan 26, 2017 10:33 am

Awesome!!!.....I really appreciate your efforts and help, thanks buddy. Sizes check out with mine so will be ordering a tire tonite. Did you fit it yourself and is there a way of doing balancing at home, I have heard of putting ceramic balls to do the job.

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CrystalPistol
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Re: Stuffing a 1500 rear end in a 1200....

Post by CrystalPistol » Thu Jan 26, 2017 10:56 am

RoadRogue wrote:Ok ,I survived the trek through the snow to the back 40 where the 1200 is housed for hibernation. It was a tight squeeze to get underneath to take the measurements but I have the requested numbers for you.
Inflated tire 6-3/4", General Tire Altimax HP
Driveshaft clearance approx 1/4" (a pencil wont fit in between)
Brake side tire to swingarm 1/2"
Total swingarm width should be 7-1/2" this is a 86 Interstate 1200.

There is absolutely NO signs of tire rub on the driveshaft tube whatsoever.

Any other questions ? Just ask! 8-)
THANKS!

When I add those numbers up, right at 7-1/2" as you say. :)
When I add my numbers up, right at 7-1/2" ..... also. 8-)
It does look to me like the 1500 FD setup / wheel / etc moves the tire center just a hair over to the brake side ... I mean "just a hair". Not a bad thing, just an observation. (Of the 9/16" added tire width, looks like you lost 2/16" (1/8) on the drive side and 7/16" on the brake side. 7/16" minus 2/16" = 5/16" ..... devided by 2 means tire center moved 2.5/16" (0.156") to left.)
Looking at specs, looks like the General 195/55-16R is 24.4" OD, near an inch shorter than the OEM tire, both new .... that would not hurt clearance either. :lol:
Nik27 wrote:Awesome!!!.....I really appreciate your efforts and help, thanks buddy. Sizes check out with mine so will be ordering a tire tonite. Did you fit it yourself and is there a way of doing balancing at home, I have heard of putting ceramic balls to do the job.
I use hard plastic Airsoft Red Jacket .22 cal pellets in my bike tires and trailer tires and narrower 70 series car tires on the rear of the Trike, dosage dependent on size. This tire above is 55 series but on the narrower bike rim, sidewalls pulled in, the tire is narrow enough that that's what I would do there as well if I were to chose this route .... I might would throw 3.5 or 4 oz. in the car tire.

Part of me is saying "stay with the plan, go Avon Cobras" as I indicated way up yonder ..... but then there is a curious side suggesting that the CT at lower cost is maybe worth a trial with my riding style in mind.

Hmmmmmmmmm ??? :?
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Re: Stuffing a 1500 rear end in a 1200....

Post by RoadRogue » Thu Jan 26, 2017 4:11 pm

The lower cost is not the reason I do this, the vastly improved traction in all conditions is the main reason I run a CT. The only time I have ever slipped a CT is in the gravel, on pavement ,wet or dry ,accelerating hard or braking hard the CT has out performed every bike tire I have ever run . The longer life and cheaper cost per unit is just a happy bonus.

The 195-55-16 is a little shorter than a stock bike tire. I chose that size for the lower gearing effect it gives me for when I am pulling my tent trailer,I live in the mountains and anytime I want to head out I am pulling some pretty steep or long grades. If you were to choose a 195-60-16 you would be very close to stock MC tire height. 8-)
Ride safe, Todd
Over night campers welcome

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CrystalPistol
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Re: Stuffing a 1500 rear end in a 1200....

Post by CrystalPistol » Thu Jan 26, 2017 5:41 pm

RoadRogue wrote:The lower cost is not the reason I do this, the vastly improved traction in all conditions is the main reason I run a CT. The only time I have ever slipped a CT is in the gravel, on pavement ,wet or dry ,accelerating hard or braking hard the CT has out performed every bike tire I have ever run . The longer life and cheaper cost per unit is just a happy bonus.

The 195-55-16 is a little shorter than a stock bike tire. I chose that size for the lower gearing effect it gives me for when I am pulling my tent trailer,I live in the mountains and anytime I want to head out I am pulling some pretty steep or long grades. If you were to choose a 195-60-16 you would be very close to stock MC tire height. 8-)
You have my attention .... by costs I simply meant it's not a huge expenditure to "try on for size". Lower gearing with a 7500 rpm redline on tap doesn't hurt.

And an inch smaller diameter is maybe why the broader tread doesn't rub the swing arm there at the corners ... the OEM rounded tire is not too far from the swing arm there at the shoulder area where the swing arm legs start inwards. Crawl under some time and you'll see. That taller 195/60-16 might rub there.
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Re: Stuffing a 1500 rear end in a 1200....

Post by RoadRogue » Thu Jan 26, 2017 9:10 pm

CrystalPistol wrote:
RoadRogue wrote:The lower cost is not the reason I do this, the vastly improved traction in all conditions is the main reason I run a CT. The only time I have ever slipped a CT is in the gravel, on pavement ,wet or dry ,accelerating hard or braking hard the CT has out performed every bike tire I have ever run . The longer life and cheaper cost per unit is just a happy bonus.

The 195-55-16 is a little shorter than a stock bike tire. I chose that size for the lower gearing effect it gives me for when I am pulling my tent trailer,I live in the mountains and anytime I want to head out I am pulling some pretty steep or long grades. If you were to choose a 195-60-16 you would be very close to stock MC tire height. 8-)
You have my attention .... by costs I simply meant it's not a huge expenditure to "try on for size". Lower gearing with a 7500 rpm redline on tap doesn't hurt.

And an inch smaller diameter is maybe why the broader tread doesn't rub the swing arm there at the corners ... the OEM rounded tire is not too far from the swing arm there at the shoulder area where the swing arm legs start inwards. Crawl under some time and you'll see. That taller 195/60-16 might rub there.

When I say lower gearing its not much but is noticeable when pulling the trailer when it comes to throttle response when passing or starting from a stop. There is probably only 300 rpm difference in 5th gear. The fun part is when running without the trailer the 1500 is a rocket off the line if you want it to be.Dusty Boots runs the 195-60-16 on his 1500 or has in the past with no fitment problems or tire rub. When I was under the 1200 last night getting those measurements I saw enough room for the 60 series tire. If you are really worried you could always run the Austone tire on the 1200, its a 175R16, little taller but narrower too. 8-)
Ride safe, Todd
Over night campers welcome

Nik27
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Re: Stuffing a 1500 rear end in a 1200....

Post by Nik27 » Sat May 20, 2017 1:14 pm

Hi all...OK fitted 1500 wheel with a 150/90-16 m/c tyre and it rubs even with the shocks pumped to max and that with brand new progressive springs fitted my wife and I added together only weigh in at 170kg (340lbs) !!
I guess I will have to go back to the 1200 wheel. The left side of the tyre rubs on the frame/mudguard mounts and the plastic part of the mudguard at the front, I cut the mudguard back as far as I can without not being able to use the mountings!! I can't think there is a difference between UK and USA GL1200's but the 1500 rear wheel runs a good inch to the left of center too.

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Re: Stuffing a 1500 rear end in a 1200....

Post by Rednaxs60 » Fri Jun 09, 2017 12:57 am

Did some research and found that the final drive reduction ratio is the same for the 1200 and 1500 at 2.833. The gearing ratios (1st, 2nd, 3rd, 4th, OD) are fairly close as well.


"When you write the story of your life, don't let anyone else hold the pen"

Ernest

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