Front Wheel Diving

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eadmr04
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Just fitted a complete new set of 10" Indian forks with shock, spring, hub etc. to my wife's Sportique frame to go with a PX200 engine I've managed to squeeze in. I had to re-grind a slot for the headset bolt as it was 90 degrees out but apart from that they seem to fit ok. Just got all the brake cable set up and just tried it out pottering up my cul de sac. When I applied the front brake it just dove straight down at the front end. I know the front brake is a bit sharp and wondered if this is normal? I was wondering if it would benefit from tapering the leading edges of the brake shoes to see if they would come on a bit more progressively rather than all or nothing? Does anyone reckon that this would be worth doing or does it sound like I might have a problem with the damper or front spring which are brand new?


Thanks in advance.
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djh66
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You may find you need a stronger spring, than standard, and/or maybe the shock is knackered?
Bring Me Sunshine COYH
eadmr04
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I got one of the stronger springs which I was going to fit to the old forks before I realised they were shot. Anyone got any tips on how to fit one of these buggers as it's about an inch longer so struggling to see how to compress it to fit it in the gap? :?
GLscoot
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I will try and describe this as best as I can. Its a lot easier with the forks out of the scooter. Yes chamfer the brake shoes front and back. Are the forks for the 10" frame, what shock have you used, I would recommend the BGM and the 25% stronger spring.

First fit the spring on the pivot bolt, screw the top plate with thread all the way down the spring so the threaded section is level with the top of the spring, force the spring into position so as the thread plate is lined up with the hole on the forks, using thick cable ties holding it in position screw the threaded plate back up the spring until it comes through the hole on the forks, as soon as you get enough thread through put a nut on. Its a two man job and using a flat screw driver to knock the plate up the spring, some wd40 or grease should help with this process. Once the thread section is sitting in place remove nut and fit penny washer and split washer.
Front shock, fit with bolt at the top first and with pressure fit the bottom bolt, the notch section on the shock rotates so once you have them lined up and in position tighten bolt. Let me know how you get on.
cartmel808
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Main scooter: 1975 Vespa Rally 200 Femsa
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eadmr04 wrote:I got one of the stronger springs which I was going to fit to the old forks before I realised they were shot. Anyone got any tips on how to fit one of these buggers as it's about an inch longer so struggling to see how to compress it to fit it in the gap? :?
SIP sell 3 different lengths in the stiffer spring for your type of fork - I think from memory 165mm being the shortest & 190/195mm being the longest.

I used the 190mm one on my Rally 200 - but on my Motovespa 150s (which looked to have an identical front end set-up) I had to use the 165mm spring?

Best to check the length of the old spring (if toy still have it) - and order the the one that best matches it in length. ;)
eadmr04
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Cheers guys.

Yes I think the forks are for normal 10" frame, they're the same length and style as the old ones that where in as it was already running with a px125 engine and 10" front wheel. I changed the forks as they where really old and pretty knackered, they had brass bushes on the pivot rather than bearings?

I got the extra strong spring and damper from Beedspeed about a year ago. Will try chamfering the pads first and see what happens and the it will have to be forks out (again) and try replacing the damper and spring.

Thanks for your advice
soulboy
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s**t shock that is mate try a sebac
eadmr04
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Right,

Changed the front shock to a new Italian RMS that I had, chamfered the front and back of the brake pads but just starts to brake and then locks completely diving right down really dangerously.

I then tried the old brake shoes from the original set up but still the same. I even then fitted the old hub with the old brake shoes but still locks completely and dives. :?

Running out of ideas now but still have a long 195mm spring which I can try and fit but think this issue is more with the brakes locking rather than the suspension?

Any ideas?
lambro
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I had a Rally in for MOT and the owner rider always rode with the front brake disconnected because of this issue :shock:
I was horrofied, as he had paid to have it fixed at the previous years MOT and when bill paid and picked up was just as bad, so he disconnected it again.
When I looked at it, it was such an obvious fault, the brake cable exits the fork leg right at the bottom, and then loops back to the back plate.
The outer was too short, and turned an almost 90 degree turn when it exited the bottom.
As soon as the brake was pulled, all slack in the outer was gone and the scoot dived so hard it tried to chuck you off.

From memory the Indian forks are the same, so have a look there before stripping everything apart.

Shaun.

On a seperate note, I also had a J in complaining about his front brake coming on for no reason whilst cornering, he had the opposite,
so much front brake cable he was riding over it on right hand bends :lol:

Both had the same previous mechanic :roll:
eadmr04
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Thanks Lambro, will try changing the cable and see. Interesting as I did shorten the cable slightly as it seemed that there was too much and it was making the cable operating very stiff. Rather have the operating slightly stiff then having it like a death trap :shock:
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